This Expert Panel is Archived.

This Expert Panel is no longer active as of December 2018. Thanks to those who posted here and made this information available to others visiting the site.

Stopping Resurgent Malaria In Mutasa Area Of Zimbabwe

Posted: 05 May, 2014   Recommendations: 4   Replies: 27

As endemic countries scale up interventions against malaria, widespread declines in burden have been reported, bringing a ray of hope that the scourge can be finally eliminated in the not-too-distant future. However, the declines have been far from universal, both between and within countries, and some areas have contemporaneously experienced increase, or rebound after initial decline.

Zimbabwe has a track record of a comprehensive malaria control programme spanning more than 60 years. Indoor residual spraying (IRS) has been the mainstay vector control approach, complemented with prompt diagnosis and treatment. Once availed funding support from the Global Fund and other partners, Zimbabwe also embarked on the current scaled up malaria interventions with vector control and ACT, resulting in substantial malaria reduction in large areas of the country, including former problem districts. However, in Manicaland Province, especially in Mutasa district, the malaria scourge proved a puzzling challenge, rebounding relentlessly the more control measures were scaled up. Most notably, the resurgence defied overlapping indoor residual spraying (IRS) and long lasting insecticidal net (LLIN) interventions.

In this virtual discussion we hear the lessons learnt from Mutasa through the voice of the national control programme personnel at the battlefront and how with partnership from the Southern Africa ICEMR team, PMI and others, the tide may be finally turning against the formidable disease.

We’re grateful to have the following panelists to lead our discussion:

     • Clive Shiff, PhD, Associate Professor, Johns Hopkins School of Public Health
     • Maureen Coetzee, PhD, Professor, University of Witzwatersrand
     • Richard Hunt, PhD, Professor University of Witzwatersrand
     • Susan Mutambu, PhD, Director, National Institute of Health Research, Zimbabwe

Our panelists will offer insight on the following questions:

1. What were the biggest challenges for controlling malaria in Mutasa district and how did the disease upsurge in spite of double intervention with IRS and LLINs ?
2. What measures were taken to address these challenges?
3. What lessons can we learn from these efforts to scale up control measures? How can these be applied to different settings and to what extent are the encountered obstacles likely to be impacting other malaria regions? etc.
4. What lessons can be drawn regarding the impact of direct partnership between research and control programmes?

We look forward to a rich discussion next week–please join the conversation and share your questions or comments for our panelists.



Clive Shiff Replied at 9:49 AM, 6 May 2014

As one of the team, I would like to set the stage for some of the discussion. Things need to be clarified for that period, First, Mutasa is on the eastern border of Zimbabwe with Mozambique. Historically there was no control in Mozambique so people world regularly cross the border to receive treatment in Zimbabwe (actually it was Rhodesia then and the Ministry of Health was well developed and active in Manicaland), This movement back and forth still happens so it is necessary to maintain a high level of vector control that is essential to prevent local transmission. Timing of this operation is critical because if interventions occur after the are warms up the visitors will infect the vectors and transmission will increase. Planning and funding the programme is vital. From 1950 until late in the 1990's, the entire malaria control programme in the country was financed by the government, and the entire responsibility of the control effort lay with local scientists and staff. So one did not have to go cap in hand to a variety of donors, each with their own agenda and restrictions to get things done. Vector control needs to be done systematically, and regularly and in Zimbabwe, one needs to take advantage of the strong seasonal transmission pattern. During the winter (june-Aug) it is too cold for mosquito activity, so transmission is very low. It is necessary to carry out IRS at this time to ensure that when conditions warm up the mosquito population is prevented from becoming active. This was the annual pattern through the Rhodesia administration and later in the Zimbabwe administration. In fact entomologists working in this area in the early 1990's had great difficulty in finding any vectors in this area. Now, not only are there plenty of vectors, but An. funestus has reemerged. This species was prevalent in the 1930's, and recorded by Leeson. By relying on ITN but not replacing these nets when the insecticide is depleted, and by being unable to conduct area wide IRS at the right time of the year, the vectors and malaria has resurged. So we need to resort to the careful planning and timed intervention. Much is in the hands of the Ministry of Health and the Ministry of Finance, so that operations can be properly planned by the authorities in Manicaland, and these need to be carried out during the winter.

j Am Replied at 10:58 AM, 6 May 2014

This is really interesting….and I'm sure this panel is up to the task.. and we hope to have some solution, or get close to solutions.
I think we have put too much weight on “evidence base” , that we tend to close our eyes, or we tend to turn our back to the “possibility of innovation” or “trying something” else.
Quite often, financial partners are the one driving programs and pointing a specific direction or approach. And most often, for the sake of accountability (rightfully), taking into account the corruption in developing countries, and/or their own other agenda , they have come to this way of doing business.

The current discussion you are launching is probably focusing on IRS and LLINs? Is there something else out there we can try to add value? Are we afraid?
The public health world, especially people working in malaria are starting talking about multisectoral approach. It’s worth trying . We know HIV fold have tried it with mix result, but it ‘s worth trying it.
Different method of prevention, etc,…. Can be checked out..

Manuel Lluberas Replied at 11:24 AM, 6 May 2014

Here’s one contribution.

We need to get away from the “malaria mosquito-only” mentality. While it is true that malaria is a significant threat in Africa, dealing only with malaria vectors is counter-productive. To the average person, a good mosquito is a dead mosquito. People don’t care if it is an Anopheles, or Aedes, or Culex, or Mansonia, or whatever. (They could not tell one from the other anyway!) When a resident of a village sees a mosquito, especially after net distribution or IRS campaign have just been completed there, the recurring thought is that the malaria control program is a monumental waste of time because they “left all these mosquitoes flying around the house” or village. While these are normally not malaria vectors, what people want is to see no mosquitoes, have a good night sleep and not have to spend so much of their meager income and limited resources on malaria and/or continue to lose family members to it.

We need to start addressing malaria vector control the way it should be: a mosquito control program. Not only we’ll be reducing malaria and giving people what they want –a good night sleep, etc.- we would also be reducing the incidence of Dengue fever, Chikungunya, Filariasis and a number of other mosquito-borne diseases affecting the population. I am not convinced that these diseases are not a factor in Africa. I am sure Dengue and Chikungunya are there and are misdiagnosed and thrown into the “malaria bag.” And incidentally, there is a significant outbreak of Chikungunya fever in the Caribbean that many think arrived from Africa in the past six months or so.

Yvan Njinzeu Replied at 12:04 PM, 6 May 2014

I agree with this contribution. Living in a dirty environment and sleeping under mosquitoes net, is not the solution. For me, the solution is very simple and we saw it while doing primary school. But for its success, the government and the populations have their own roles (working hand-in-hand). The government's role will be to improve the life's quality of its population (in sociology, we use to say that disease has a social origin) and the population have to fully participate by applying resolutions.

Maureen Coetzee Replied at 1:42 PM, 6 May 2014

Let me begin by addressing point no. 1 above - why has there been an upsurge of malaria in Mutasa District despite the double intervention of IRS and LLINs. The answer is quite simple - both these interventions have been utilising pyrethroids and since the Anopheles funestus populations in the area are highly resistant to pyrethroids, of course the interventions have had little or no impact on malaria transmission.

Many people under-estimate the importance of An. funestus in the transmission of malaria parasites, mainly because in West Africa it tends to be relegated to 'minor' vector status compared with Anopheles gambiae. In many parts of eastern and southern Africa, however, it is by far the most dangerous vector that we have. The Plasmodium falciparum parasite is very well adapted to An. funestus and the vector appears to suffer no adverse affects through being infected. Infection rates recorded in An. funestus far out-strip anything recorded in An. gambiae. For example: 22% in South Africa (De Meillon, 1933), 7% in Zimbabwe (Meeser, pre-WWII), 9% in Uganda (Gibbins, 1932) and more recently 6% and 11% in Tanzania (Temu et al 1998 and 2007 respectively). With these levels of infections, very few funestus mosquitoes can end up causing an awful lot of malaria cases. Another confounding factor is that the preferred breeding habitat of An. funestus is permanent swamps and streams, meaning that it does not totally disappear in "winter" and low-level transmission continues in the dry months (this was noted by De Meillon way back in the 1930s).

Then, in addition to having a super efficient vector, the An. funestus population in southern Mozambique developed resistance to pyrethroids in the 1990s (reasons for this are unknown). When South Africa stopped using DDT and shifted to pyrethroids in 1996, it took only 3 years for this country to experience the worst epidemic since the 1930s. Pyrethroid-resistant An. funestus mosquitoes were collected in 1999 (one An. funestus per five houses) with an infection rate of >5%. Also in 1999, An. funestus from Maputo in Mozambique was shown to be resistant to pyrethroids (and carbamates). This resistance has now spread throughout Mozambique, Malawi, northern Zambia and almost certainly is into Tanzania. Zimbabwe has not escaped and those areas in the east bordering Mozambique have populations of An. funestus that are resistant to pyrethroids.

The mainstay of mosquito control interventions such as IRS, LLINs and larviciding, is the use of EFFECTIVE chemicals - i.e. chemicals that will kill the mosquitoes. If the mosquitoes are resistant to pyrethroids and are no longer killed by this class of insecticides, then pyrethroids are no longer effective and different chemicals from different classes of insecticides must be used. It's that simple.

From the results that we have on insecticide susceptibility of the Honde Valley An. funestus populations, DDT and organophosphates give 100% kill and could be considered for IRS. Carbamates, while not being as good as the other two, could possibly be used later in a rotational system in order to manage the resistance problem. A resistance management programme would also address Manuel's comments above about "mosquito control" because many of the culicine mosquitoes are also resistant to pyrethroids and would presumably be knocked out by a sensible use of alternative insecticides but proper susceptibility testing needs to be done on the culicine populations as well.

What is needed now, in addition to that mentioned by Clive above, is a very strong advocacy programme to educate the communities about vector control and malaria transmission and the difference between Anopheles and culicine mosquitoes.

An entomological survey of other malarious areas in Zimbabwe is urgently needed to determine the extent of the distribution of pyrethroid-resistant An. funestus. In addition, the other endemic vector in southern Africa, An. arabiensis, should not be neglected.

If anyone is interested in publications on the above issues, let me know and we will try to help.

Marie Connelly Replied at 2:11 PM, 6 May 2014

Many thanks to everyone for beginning such a robust discussion! I did want to clarify that this Expert Panel discussion is actually taking place next week, May 12-16. These dates were initially posted incorrectly, so I apologize for the confusion.

In the meantime, of course, you are more than welcome to share questions or comments for our panelists to address when we begin the discussion next Monday, May 12th.

We are also pleased to share that Dr. Susan Mutambu, PhD, Director, National Institute of Health Research, Zimbabwe will also be joining us as a panelist.

My apologies again for the miscommunication—we look forward to a rich discussion next week!

Sungano Mharakurwa Replied at 4:29 PM, 6 May 2014

Greetings to All and thanks Marie. I am glad to add that we may also have the Manicaland Provincial Medical Director (PMD) joining the panel, subject to confirmation. So we should hear from both the control program as well as research community. Great contributions so far and so many lessons already!
May I also add that apart from extensive experience with malaria mosquitoes in Africa, including Zimbabwean vectors, Maureen Coetzee and Richard Hunt are actually working on vectors from Mutasa itself right now including current status of insecticide resistance in the area (in preparation). Looking forward to good discussion!

j Am Replied at 4:20 AM, 7 May 2014

This is really interesting….and I'm sure this panel is up to the task.. and we hope to have some solutions, or get close to solutions.
I think we have put too much weight on “evidence base” , that we tend to close our eyes, or we tend to turn our back to the “possibility of innovation” or “trying something” else.
Quite often, financial partners are the one driving programs and pointing to a specific direction or approach. And most often, for the sake of accountability (rightfully), taking into account the corruption in developing countries, and/or their own other agenda, they have come to this way of doing business.
The current discussion you are launching is probably focusing on IRS and LLINs? Is there something else out there we can try to add value? Are we afraid?
The public health world, especially people working in malaria are starting talking about multisectoral approach. It’s worth trying. We know HIV fold have tried it with mix result, but it ‘s worth trying it.

The multispectral Approach to tackle malaria encompasses some of the concerns here (such as the social and economic issues)
Different method of prevention, etc, Can be checked out.
As the same time it's worth pursuing the “technicalities” such as studies on the vectors( mosquitoes the human
J. Amouh

Sungano Mharakurwa Replied at 1:16 AM, 12 May 2014

In following up this discussion, the first question: "1. What were the biggest challenges for controlling malaria in Mutasa district and how did the disease upsurge in spite of double intervention with IRS and LLINs?" seems to have been comprehensively addressed already. The basic reference paper (attached) shows clear efforts to scale-up malaria control in Mutasa District as anywhere else, including switch to more accurate diagnosis; more effective treatment drugs (ACTs); and double IRS and LLIN vector control intervention (both based on synthetic pyrethroids). Nothwithstanding, the malaria situation overall seemed to escalate and appeared to continue to doing so to the current malaria season. It would be good to hear from the control programme representatives, but ironically during data collection, the research team, in working closely with the control department, observed that the operations in Mutasa were exemplary in terms of timing and intervention targets as well as coverage, yet malaria kept resurging more than defiantly. Dr. Mutambu, as research arm of the Ministry, would you know of any major challenges on control faced in Mutasa?

This brings us to the findings shared by Prof Coetzee. It appears still widely believed that insecticide resistance may or may not make much difference on effectiveness of malaria control (Gatton et al 2013; Rivero et al 2010). Are we seeing the public health impact of insecticide resistance in Mutasa, as happened to South Africa in 1999? With emerging insecticide resistance in several parts of Africa (Chanda et al 2011; Abilio et al 2011; Wondji et al 2012), what may this mean for other countries in the region?

Attached resources:

David Zinyengere Replied at 7:11 AM, 12 May 2014

the situationMay i take the opportunity to thank you all for such informative and probing analysis of the Mutasa situation. I feel this is a proactive way that could help formulate a potential solution for the area.
I have had a good opportunity of working in the area over the last two seasons while doing some consulting on various malaria control issues including environmental compliance issues. One element that i have observed is that the area has experienced tremendous small scale agricultural activity over the last few years(3-5 years). In all our efforts i also feel that these activities need to be considered in mapping out whatever strategies we come up with. In all these activities there has been a wide scale use of a range of pesticides and one may also hazard a general hypothesis that these activities may have played a significant role in the emerging resistance within the district.

Pierre Bush, PhD Replied at 1:49 PM, 13 May 2014

Dear Colleagues,

Thank you for this great discussion. The effort to eliminate malaria requires to combine several measures: IRS, use of LL INS, mass educational campaign at the household level, and adequate infrastructure in rural areas. It would be completely futile to conduct IRS when there are conditions that allow mosquitoes to breed and grow. Elimination of the factors that allow mosquitoes to multiply must be eliminated first. The population must be educated on how to control mosquitoes growth and multiplication. During the rainy season, there should be proper water flow so that there no water accumulation around the homestead (household). All the dams and other free standing must be sprayed so that mosquitoes are deprived of habitat. Local authorities must be very proactive in public health education. Otherwise we will be wasting resources on IRS and LL INS. The Western countries eliminated malaria bu get rid of mosquitoes. That is what we need to do.
Thank you for these sound ideas.

Mercy Mukorera Replied at 5:14 PM, 13 May 2014

Thank you for this interesting discussion. I appreciate all efforts that are made to control malaria in Zimbabwe. I also realise that in most of our disease control activities, there is a serious and wide gap between the disease control program responsible for implementation of activities and the research community. Firstly, it would have been more valuable to study and evaluate the process of IRS or bednet distribution and use, to be able to answer the pertinent question of why the desired outcomes are not realised. Evaluation of the implementation process is key to answering different questions, even other contextual factors that may be barriers to disease control interventions can be realised.
Resistance to pyrethroids could be one issue, but is there guarantee that introducing a different intervention would work?? What about commitment from programme managers (I am not talking about the National Malaria Programme people in Harare) I mean to PMD, PEDCO and district level. When planning and evaluating, these stakeholders become very important as they are the people directly responsible for implementation.
What about community participation? How can the community be engaged to be part of decision making, research, and behaviour change?
What about other larvicides or mosquito repellents?

A/Prof. Terry HANNAN Replied at 5:47 PM, 13 May 2014

Marie, this discussion has taken off because it is so interesting. People could just not wait until the 12th. For myself already the educational value has been immeasurable. Not being an infectious disease physician and I live a cold climate some of the issues raised are not relevant to my dial work. One point did stand out was the use of nets over beds. From my understanding of the work in Eldoret (AMPATH) nest with other technologies were significant in malaria control.

Sungano Mharakurwa Replied at 6:08 PM, 14 May 2014

Hi Colleagues,
You raise some interesting issues and hopefully our panelists will soon share some thoughts and experiences. David, your observation is curious and well worth following up. The question is whether agriculture is to blame, while on the other hand some have pointed a finger at ageing nets/washed nets with sub-lethal chemical. So much to learn out there!
As for other measures, these are very important to consider too. If they work and are acceptable, we want to throw every weapon we have at this scourge. The interesting thing though is that during the years of DDT and chloroquine, malaria was well under control in Mutasa! Now that we have better drugs (ACTs), new insecticides for IRS and nets (which were not there), more trained personnel...

Clive Shiff Replied at 8:51 AM, 15 May 2014

Dear Colleagues:
I have been following all the discussion, and see names of old friends, (David Zinyengere) and now Ronnie Masendu. Ronnie did his PhD research on the mosquito populations in Zimbabwe in the 1990's and found very few vectors. Please confirm this Ronnie. The reason was that the country had a good health infrastructure and a reasonably effective programme of IRS. As I recall, there were no An. funestus in the Honde Valley/Mutasa area, and not many (<50) An. gambiae (sl) in the whole Eastern district area. ( An. funestus, which is resistant to the pyrethroid insecticides is now common in this area in significant numbers, (as are the an An. gambiae complex, but they are more susceptible to the insecticides). It is important to point out that An funestus is now common in South Africa, part of Zambia and in Kenya too, all places where ITN are (or were) used. The Zimbabwe disaster happened in 1997-8 when the Ministry of Health was stripped of resources and almost collapsed for nefarious internal reasons. So the point I want to make is that sustained malaria control can only be effective if there is a functional MoH. It is in fact a public health procedure and as such is an ongoing priority of control and surveillance. To talk about education, the population in most of the country knew about malaria and regular IRS was done annually from the mid-1950's until the late 1990's. They knew, but as there wasn't much evidence of the disease, people got complacent, and often the spray teams were locked out. IRS is very disturbing, imagine being told by a team of strange men that you must move all your furniture from the house, so they have access to all walls, even remove pictures, etc. Then the walls are sprayed with a white liquid that may be a bit odourous. AND for all this you had to collect, from nearby wells etc there are no water taps!, about 40 litres of clean water for the spraymen to mix the insecticide. In Zimbabwe, at least two generations have grown up without the scourge of malaria so people didn't even think of the problem. However, with the return of malaria ITNs really solved the spraying concern but as we now know, the insecticide wears off, and so does the efficacy. So here we are again. It is important to concentrate on the re establishment of an effective Ministry of Health or what ever is done by donors, expatriates et alia will not be sustained. Public Health is a domestic issue. One can get advice, but the work is done by dedicated trained and properly remunerated personnel. There is no magic bullet. The politicians and government must wake up, get out of the Mercedes and go by foot to the people and the problem.

Maureen Coetzee Replied at 12:51 PM, 15 May 2014

Dear All, there are several comments above that need to be addressed and they all hinge around an understanding of the mosquitoes that transmit malaria and what we can do about controlling them. Without effective vector control, malaria incidence will not drop!

"trying something else" - the current control methods that we use (IRS and ITNs) are highly effective if they use insecticides that will kill the mosquitoes and, in the case of ITNs are properly used by an informed community. If the mosquitoes are resistant to the insecticides, then the mosquito control interventions will fail unless the programme management changes their choice of insecticide to one that works. In the case of ITNs, there is no other option right now other than pyrethroids (but this might change soon). IRS, on the other hand, can make use of insecticides in 4 different classes of insecticides and this should be the strategy employed by the MOH - called 'resistance management' and supported by WHO with documentation on how to go about doing this.

So before a programme "tries something else", it really needs to get its mainline vector control interventions operating properly.

"insecticide resistance may or may not make much difference" - this debate mostly rages around the efficacy of bed nets. However, we know from the literature that IRS failed in South Africa when pyrethroid resistant An. funestus returned to the country. We also know that IRS with DDT has failed in Ethiopia. So when, in Honde Valley, you get large numbers of pyrethroid-resistant An. funestus being collected in March in houses that were sprayed with pyrethroids in November/December and these houses ALL contained long-lasting insecticide treated bed nets, then you must know that your vector control interventions with pyrethroids are failing. Furthermore, when you find that in the 8 homesteads that you visited to collect your mosquitoes, almost every single person living in that homestead had had a bout of malaria at least once in the preceding 4 months, then you know that the vector control interventions are not working! Our mosquito surveys are providing essential information to guide the control programme strategies and hopefully influence policy changes to deal with the problem.

Apportioning blame for the resistance seen in mosquitoes to the agricultural sector is not supported by data and does not help resolving the situation in the short term.

"futile to conduct IRS when there are conditions that allow mosquitoes to breed and grow"- the reason that IRS has been used globally since the 1950s is because it reduces the longevity of the vectors. This means that the female mosquitoes do not live long enough to allow the parasites to complete their developmental cycle inside the mosquito. It actually doesn't matter how many potential mosquito breeding sites are around as long as you are killing off the adult females before they can transmit malaria. Killing off the females also impacts on their reproductive potential and so you will have less mosquitoes laying eggs and breeding through to adults. It is only at this point, where the populations are significantly reduced, that larviciding or "other" methods may play a role.

"resistance to pyrethroids is one issue" - I'm afraid that pyrethroid resistance is the WHOLE issue right now. And it is not just Zimbabwe that has to deal with it - Mozambique, Malawi and Zambia are in similar situations.

"during the years of DDT" - Clive's comments underline the need to use EFFECTIVE insecticides and to use them in a sensible resistance management programme. When this is done, the malaria incidence will drop!!!

John Spurrier Replied at 2:46 PM, 15 May 2014

I have followed this discussion with interest. I am a bit surprised that with the topic listed as stopping resurgent malaria all the discussion has been on LLINs and IRS and environmental factors affecting the mosquitoes. Maybe I missed something and this discussion is limited to the mosquito side of things. There has been no discussion on the treatment side. Early on someone suggested that it would take a multisectoral approach which I would think should included the patient as well as the mosquito. As Clive Shiff and Sungano Mharakurwa well know, a big factor in the significant (>95%) reduction in malaria at Macha in Zambia has been treating asymptomatic carriers. It would seem to me that this should be part of any effort to stop resurgent malaria.

Lovemore Gwanzura Replied at 6:43 AM, 16 May 2014

Hi Dr Spurrier. i totaly agree with a multisecterial approach of meeting the TOPIC solution. treating , biological or insectcide use for the control of the vector, treatment of patients and carrier etc requires long term strategic plans which also requires trainied human resources, approprite equipment and of course finances for sustainbility.Mutatsa in Zimbabwe unlike Macha in Zambia is confounded by the direct negative effects of "SANCTIONS" i am not hiding behind a finger but this is reality. most well trained manpower to the level of teacher( representing community leaders) doctors, nurses and EHT left for grener pastures in our neighbouring countries nad abroad. I leave this to you all to think about it, please remove the Political MASK and see this as reality which has and will continue confounding the idea of stopping malari ain Mutasa.Experts in this health field have and continue to experience frustration when they embark on thier duties resulting into a rapid "staff turnover" zimbabwe is beautiful and requires now FINANCIAL support direct into the hreath system not via some NGOs who in their part have done splendid job but adirect input into the gOVT system will be the best. I hope Dr Spurrier will also agree with me because they have a functional sytem which we can easily implant here in Zimbabwe and reduce the malaria to an acceptable level thank you.

Lovemore Gwanzura Replied at 11:41 AM, 17 May 2014

HI Sungano! last time we had problems of Seually transmitted diseases /infections , some sites in africa tried novel activities which had a three fold impact in the reduction of the incident of many of the aetiological agents. Can we try using a similar model for the reduction or stopping Malaria in Honde valley. Medication is now simple and nearly everyone can take it with less supervision. How about using a mass treament compaign Technique. Which drug to use may now be a point of discussion. I will try to answer some of the questions you posed in your presentation of the subject later.


David Zinyengere Replied at 3:03 PM, 17 May 2014

Dear All
This discussion is certainly getting very thought provoking .Some interesting elements of malaria control strategies need to revisited
With the intention of evaluating what we have done and the way we did it , what we are currently doing, how ,when and why? It may sound obvious or too simple but there are issues that we have may taken for granted as the programme was evolving over the years. In the earlier days the programme was very inclusive of all stakeholders -not sure if it still is- and there were evaluation debriefing workshops at strategic time points to ensure that all the relevant and potential emerging issues would be addressed before they developed into insurmountable challenges.
On the other hand , we may not blame the agricultural activities as pointed out by Maureen but in our insecticides and entomological evaluations lets not entirely relegate this fact asside because the negative effects of agricultural pesticide activities in relation to public health have been noted elsewhere in the continent. However the reality is that ,resistance in the vector has been established and there is need to address this challenge before it gets worse .
Would it be asking for too much if one proposes that a resident workshop to address this issue is initiated to enable a timeous action plan is mapped out .

Ron Masendu Replied at 11:06 AM, 21 May 2014

The discussion on malaria in Mutasa, and Manicaland is interesting indeed. We made the following observations:
a) entomological
i) that the residual efficacy of the pyrethroid (lambdacyhalothrin) used in IRS was low (mortality after 24-hr holding period was at 49%) 13 weeks post-spray
ii) zero mortality was recorded with A. funestus exposed to lambdacyhalothrin.
b) socio-economic

Clive Shiff Replied at 11:23 AM, 21 May 2014

Dear Ron:
I am anxious to get some information from you. When you did your thesis work if I recall properly you did spend time in the Eastern Districts, and the vector species population was sparse, is this true, do you have numbers and whether you found funestus in your work??
best wishes
Clive Shiff

Ron Masendu Replied at 11:37 AM, 21 May 2014

Apologies for the incomplete message above.

On the socio-economic front we observed that numerous homesteads have started banana plantations as out-growers for big firms. The bananas are irrigated regularly and this translates into increased availability of water. Bananas were grown in Mutasa before, but the scale has changed drastically. I suspect this change in land use is contributing to the presence of An. funestus and the upsurge in malaria cases. Outdoor transmission is enhanced though increased human behavior as people work in the fields late in the evening or early in the morning. Besides IRS, ITNs, treatment, An integrated approach is called for that involves working with the communities to increase their knowledge and level of participation in disease prevention. So far, the communities cooperate during IRS as evidenced by the high IRS coverages. Mass distribution of LLINs may be done, but the ultimate consistent use of the nets at household level remains largely an unknown factor and the effectiveness of nets is compromised by insecticide resistance. Mosquito repellents could be introduced in the communities in the affected areas.

After noting pyrethroid resistance, OPs have been recommended for IRS. This is an expensive alternative and its effectiveness and acceptance by the communities remains to be seen.

For me, one key lesson from the Manicaland experience is that control programs need inputs from and confidence in research. Research needs funding. Funding remains a challenge.

Ron Masendu Replied at 11:49 AM, 21 May 2014

Hi Clive,
We spent more that two years searching for the vector in Honde Valley with funding from WHO. We hardly collected anything from indoor resting collections using the standard PSC, pit shelters and exit window traps. Larval surveys are just frustrating if one has experience with An. gambiae. We had camps in more than four areas but, still we did not record any An. funestus. Disturbingly, one or two of our guys stationed there went down with malaria despite this apparent absence of vectors! Even now, it is fairly easy to miss the An. funestus if one is not meticulous. As for the records, data should be available at NIHR. I could follow up with Susan.

David Zinyengere Replied at 2:43 PM, 21 May 2014

Hi Ron
You aptly described the situation as it pertains to the Manicaland- Mutasa District challenges. It sometimes baffles the well intended researcher. Once again I reiterate the point i raised in my earlier posting that there is a need for multisectoral approach to address this challenge. This will enhance the efforts of research and the subsequent funding support required . One other aspect that i would like to find out is whether any evaluations have been carried out on the seasonal patterns(with particular emphasis on temperature and rainfall ) over the years in relation to the disease trends

Idongesit Ukpe Replied at 10:41 PM, 21 May 2014

Dear Ron,

Is the outdoor transmission 'theory' or 'hypothesis' suggested or supported
by case investigation reports?

Sungano Mharakurwa Replied at 4:18 PM, 23 May 2014

Great questions, just like quite a few others that emanated from this discussion. So many lessons and definitely more as yet to learn from the fight against the formidable scourge that is malaria. With all the challenges, Mutasa is also an illustration of how local partnership between control (NMCP) and research programmes (such as the Southern Africa International Centre of Excellence for Malaria Research (ICEMR); National Institute of Health Research (NIHR); Biomedical Research and Training Institute (BRTI)), and other private partners (PMI, Abt etc.), can be brought to bear on a daunting public health problem. From the experiences and research findings shared, especially entomology, it appears that the tide may be about to turn. Hopefully, one day we can also share a turnaround story similar to Macha, southern Zambia, where malaria was dramatically reduced after initially ravaging local communities for decades.

Many thanks again to our panelists and community members who participated in this rich discussion. We greatly appreciate the ideas and insights shared here. We will be working on a Discussion Brief to summarize the key points from this discussion, and will share details as soon as that is available on the website.

This Expert Panel is Archived.

This Expert Panel is no longer active as of December 2018. Thanks to those who posted here and made this information available to others visiting the site.