Posts or Comments 20 July 2024

Monthly Archive for "April 2013"

ITNs &Mosquitoes &Surveillance Bill Brieger | 26 Apr 2013

Malaria Vector Bionomics During the Dry Season in Nchelenge District, Zambia

Smita Das and Douglas E Norris of the Johns Hopkins Bloomberg School of Public Health Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute have written our guest blog posting based on a poster they presented at the recent JHU Global Health Day.

picture1-smita-das-and-douglas-norris-jhmri-sm.jpgAs part of the International Centers of Excellence in Malaria Research (ICEMR) in Southern Africa project, mosquito collections are being conducted in Nchelenge District in Luapula Province, Zambia. Nchelenge experiences hyperendemic malaria despite continued implementation of indoor residual spraying (IRS) and long-lasting insecticide nets (LLINs) as control measures.

Center for Disease Control light trap (CDC LT) and pyrethroid spray catch (PSC) collections performed during the wet season in April 2012 revealed the presence of both Anopheles gambiae s.s. and An. funestus s.s. Both species were highly anthropophilic and the Plasmodium falciparum sporozoite infection rate in An. funestus was higher compared to An. gambiae.

In the dry season collections, An. funestus continued to be the dominant species with even fewer An. gambiae caught compared to the wet season.  Due to the abundance of An. funestus and high human malaria infection rates in Nchelenge, it is predicted that the human blood index and entomological inoculation rate for An. funestus is higher than that of An. gambiae in both seasons.

The multiple blood feeding behavior and insecticide resistance status of both malaria vectors will also be explored as this can give us an idea of estimating the transmission potential of these mosquitoes. The vector data in Nchelenge present unique opportunities to further our understanding of malaria transmission and the implications for malaria control in high-risk areas.

Advocacy &Funding &Health Systems &Procurement Supply Management &Universal Coverage Bill Brieger | 25 Apr 2013

Appreciating Many Years of Malaria Partnerships and Investment

wmd2013logo-sm.jpgWhile today it technically the sixth World Malaria Day, one should actually trace the origins back 13 years to the first Africa Malaria Day (AMD) in 2001, held to encourage progress based on the Africa malaria Summit in Abuja just one year before.  And since the Abuja summit and its resulting declaration were backed by the Roll Back Malaria Partnership, which formed in 1998, one could say the world has 15 years to considering in judging progress in and plans for partner investments in ridding the world of malaria.

In 2001 organizers of Malaria Day events were encouraged to feature a ‘new’ medicine that WHO said could save 100,000 child healths annually in Africa. artimisinin-based combination therapy (ACT) drugs are now the front line treatment in most all endemic countries, and deaths have declined somewhat on the order of 400,000. At that time there was only one major manufacturer of ACTs. Investments by pharmaceutical companies in generic ACTs now means that there are at least nine companies that produce prequalified ACTs. What is needed is more indigenous African pharmaceutical companies approved to invest in ACT production.

logo_animated.gifThe first AMD stressed the risk of malaria to pregnant women and recommended widespread use of Intermittent Preventive Treatment in pregnancy (IPTp).  This recommendation has been adopted in countries with stable falciparum malaria transmission, but has lagged in terms of implementation, and coverage still lags below the 80% target set at the 2000 Abuja Summit.  There are missed opportunities to provide IPTp at antenatal clinics due to stock-outs, provider attitudes, and client beliefs. Weak health information systems mean that even when services are provided, reporting may not accurately reflect true coverage of IPTp.

In the meantime resistance is growing to sulphadoxine-pyrimethamine (SP), the drug used for IPTp in part due to the inability or unwillingness of country drug authorities to curb its inappropriate use for case management.  WHO now recommends more that the original two IPTp doses and suggests that pregnant women get SP at each ANC visit after quickening.  In the meantime research is underway to find substitutes for SP.

The first AMD addressed the role of insecticide treated nets (ITNs) in helping halve the world’s malaria burden by 2010.  Major progress came in 2008 when the whole United Nations community and of course companies invested in net production got behind universal coverage. In addition the advent of the long lasting insecticide-treated net with insecticide infused in the fabric from point of production pointed the way to success.

These three core interventions – ACTs, IPTp and ITNs – have been strengthened with better diagnostics and a variety of other vector control measures, Hopes for a vaccine still remain a dream, though an achievable one.  While we have high expectations for eradication, we can see that some of the health systems challenges that thwarted the first malaria eradication effort are still with us including weak procurement and supply management, inadequate human resources and gaps in health information systems.

The foregoing implies that we need at least two forms of future investment in malaria. First is investment by governments in strengthening the health system that deliver malaria services. The second investment is in continued biomedical research in order to fend off resistance by mosquitoes and parasites and of course social research to address issues of behavior, adoption of innovations and program management practices. Let’s hope that when World Malaria Day 2014 rolls around, we can measure these increases investments.

Elimination &Surveillance Bill Brieger | 24 Apr 2013

Investing in Foresight, not Just Hindsight for Malaria Elimination

wmd2013logo-sm.jpgThe 2015 Millennium Development Goals milestone of reducing malaria morbidity and mortality is sometimes hard to see from here because of the many carts that got ahead of the horses and clogged the road.  We discussed earlier this week about the big push for universal coverage with long lasting insecticide-treated nets that got ahead of thoughts and plans for disposing the net packaging as well as old nets in an environmentally sound way.

Only a few efforts are underway to find a solution to old net disposal. In fact the need to replace LLINs much sooner than expected because of less than desired durability in real life field settings was another cart that surprised some horses and may lead to stock-outs in the next few years as financial sources for nets are not as certain as before.

A classic example ‘carthorsology’ is the roll out of artemisinin-based combination therapy medicines long before appropriate, easy to use diagnostic procedures were in place. Certainly we needed to save lives, but while most endemic African countries replaced first line drugs to which parasites had developed resistance with ACTs between 2005 and 2008, there was no alternative to clinical diagnosis in place.

Hopes that net use and other preventive measures would bring down the demand for ACTs were thwarted when health workers had to rely on their clinical judgment and continued to prescribe the more expensive ACTs presumptively just as they had done for the cheaper chloroquine and sulphadoxine-pyrimethamine. When RDTs finally became more common, there was an uphill battle to convince health workers that their clinical diagnosis was no longer acceptable.

In actuality, RDT supplies are still not matching need – i.e. enough to test all fevers and suspected cases of malaria. So in hindsight we are rushing to invest more heavily in RDTs and health worker diagnostic training and trying to find ways to safely dispose old nets.

roadmaps2012.pngProcesses like RoapMap planning sponsored by RBM and WHO are certainly moving us in the right direction that views holistically the totality of the malaria intervention package intervention. One wonders though if any other carts lie unforeseen ahead to block our horses.

One example of needed foresight is the development of appropriate strategies for end game pre-elimination and elimination.  In particular are appropriate surveillance systems in place?

Donors, especially the Global Fund seem reluctant to support the challenges of pre-elimination in countries like Swaziland, Namibia, Solomon Islands and others who are on the frontline of the elimination effort.  Fortunately the Clinton Health Initiative is one of those with foresight.  Hopefully we can keep investing in the forward march without additional unforeseen diversions in the RoadMaps.

Epidemiology &Surveillance Bill Brieger | 24 Apr 2013

Household Survey Used to Study Human Population Movement on Malaria Transmission in Southern Zambia

Karen E. Kirk, a MSPH-Internal Health Candidate at the Johns Hopkins Bloomberg School of Public Health has written this guest posting based on a poster she presented at the School’s Global Health Day earlier this month.

The inability to eliminate malaria in low endemic settings due to importation by infected individuals is considered a potential barrier in the fight to eradicate malaria worldwide.  Individuals living in the rural Choma District, Southern Province, Zambia have seen a dramatic decline in malaria since 2007 with the implementation of malaria control programs that include active case detection; mass distribution of insecticidal treated nets (ITNs); and widespread use of indoor residual spraying (IRS).  However, malaria elimination has still not been achieved in this region of the country.

blog-kirk-field-staff-collecting-blood-samples-2.jpgThe first photo shows field staff collecting blood samples from household members to test for malaria parasitemia in Choma District

A household survey was conducted in the Choma District to assess human population movement (HPM) and its association with confirmed or suspected malaria cases of individuals living in the district. The survey looked at travel history of 196 individuals from 42 randomly selected households between December 2012 and March 2013.  It collected data on travel patterns of individuals from the previous 4 weeks who stayed overnight for at least one night outside of their village. In addition, it collected blood sample for the testing of malaria parasitemia.  This survey was included in both the longitudinal and cross-sectional household surveys being conducted by the International Centers of Excellence in Malaria Research (ICEMR).

blog-kirk-community-survey-2.jpgThe second photo shows Field staff conducting malaria community health and HPM survey with mother in Choma District

Of the 196 individuals surveyed there were 97 (49.5%) adults (ages >17), and 99 (51.5%) children (<17).  There were a total of 34 trips taken by 31 (15.8%) individuals, 18 adults and 13 children. The majority of these individuals (59.3%) traveled for 7 days or less and 27 (87.1%) individuals traveled within the Choma District.  No malaria cases were detected in this study and therefore the results of this preliminary data were not able to show an association between HPM and malaria incidence rates.  However, with an increase in data collected over time, trends could be ascertained to determine seasonal patterns with HPM and its impact on malaria incidence rates in this hypoendemic setting.  The hope is that with adequate funding in malaria research with HPM, these types of studies can contribute important information on malaria transmission and help achieve the goal of regional elimination and ultimately eradication of this harmful disease.

[Bill Moss of JHSPH served as Principal Investor of this project]

Environment &Integrated Vector Management &Vector Control Bill Brieger | 22 Apr 2013

Malaria Control and Earth Day: are they compatible?

Clearly no one wants to argue against efforts to curb a deadly disease. The question is whether the approaches to doing so have any negative consequences that can be easily ameliorated.

dscn7103-sm.jpgVector control gets the most attention. One concern is the plastic bagging in which long-lasting insecticide treated nets are packaged. Rwanda, which has outlawed commercial use of plastic bags for shopping, is taking the LLIN packaging seriously.  The photo shows net packaging that has been removed at a health center and stored for later incineration. Clients take their nets home in paper bags and are encouraged to hang them immediately.

Another net concern is disposal of old, used, damaged nets. LLINs do not have under ‘normal’ conditions the 5-year lifespan originally hoped. Plans for proper disposal are not fully developed in most settings, but the massive distribution of nets to achieve universal coverage from about 2009-12 are about to need replacement. It is possible that some of the net misuse reported in the media is actually repurposing of old nets. More information from communities and local health authorities is needed.

Insecticides for indoor residual spraying usually are the first thought that comes to mind concerning environmental impact of malaria control. While arguments primarily focus on DDT, it is important to note that WHO has approved over a dozen different insecticides for IRS.  The problem is not so much the use of chemicals for actual IRS, but the misuse outside approved spraying programs for farms and fish kills. At present IRS is a highly geographically focused activity in most countries, and control of the activities seems to be working for the large part, but even the process of preparing for and cleaning up after a spraying exercise can results in spills and contamination. Guidelines exist, but are they followed?

dscn3829sm.jpgThen we get to the issue of medical waste from rapid diagnostic tests.  Some health centers sharps and waste boxes for short term disposal and as pictured here in Burkina Faso, have incinerators tor final disposal.  Community health worker use of RDTs is usually accompanied by sharps and disposal boxes that can be returned to health centers.  All of this needs careful monitoring.

One must even think about packaging of artemisinin-based combination therapy medicines which are prepackaged by age group. These packets are small and are sent home with patients and care-givers. The paper may be burned or composted, but there are also plastic blisters in the packet. This may not account for much on an individual family basis, but on the community level it may be substantial.

dscn3738-safety-box-sm.jpgReaders may think of other environmental concerns from their own experiences and share success stories for environmental management accompanying malaria control in their countries.  So, as noted, we will not stop malaria control efforts on Earth Day, but at least we can be more conscious of the materials used, whether they can naturally decompose in the environment and thus make some contribution to a healthier planet.

Funding &Indoor Residual Spraying &ITNs Bill Brieger | 20 Apr 2013

Nigerian Lawmakers Skeptical at Time When More National Malaria Support Needed

mip-nigeria-sm.jpgAs global financial support for malaria and other disease control efforts has faltered, there is a greater need for national malaria programs to pick up the slack. A look at Nigeria’s national health accounts does show that ‘foreign’ aid does play a relatively small role in health financing and expenditure in this oil-rich country, but ironically it is the common citizen who picks up the bulk of health financing through out-of-pocket expenditures.

The question of local initiative in the move toward elimination of malaria received a severe blow when the Nigerian Senate Committee on Health questioned the need for continued purchases of long lasting insecticide-treated nets (LLINS). The Guardian newspaper reported that the, “Chairman of the committee, Dr. Ifeanyi Okowa, wondered why Nigeria would still continue to cling to the strategy, which he said was not working, when country like Senegal that has manufacturing plants for LLINs was using other effective means to tackle malaria.”

The Senator’s views contrast with those of national experts and the WHO: “While the Minister of State for Health, Dr.Muhammad Ali Pate, said in January that the ministry proposed N1.8 billion for the procurement of LLINs for additional three states, a World Health Organisation (WHO)’s report shows that Nigeria would need one billion dollars (N158 billion) to stave off backsliding and resurgences of malaria in 2013 and 2014.”

It would seem that the Senator was reacting to perceived pressure from the international community to maintain a malaria control strategy that he thought was less effective than indoor residual spraying (IRS).  Of course one of the biggest challenges in disease control advocacy efforts is to educate policy makers. The Director-General of the Nigerian Institute for Medical Research, Prof. Innocent Ujah, tried to do this. He pointed out cultural factors that inhibit net use – and in fact lack of serious community follow-up efforts after massive net distribution over the past 2-3 years, can be traced as one reason why LLINs may have been wasted.

The Senator did not realize that malaria control leading toward elimination needs a multifaceted strategy. IRS can be part, but has its own limitations of which one is expense.  In highly endemic, stable and year-round transmission environments like Nigeria, spraying would be needed twice a year.  We forget that Nigeria has already once tried IRS a few decades ago and abandoned the effort in part due to the huge logistical challenges required.

Nigeria has tried selling LLINs/ITNs through the private sector, but coverage was low since not all Nigerians could or would buy them despite paying disproportionately out-of-pocket for treatment. If the government refuses to fund massive LLIN distribution, then we can expect the burden to fall on the common people who may die from malaria before they purchase a more costly net on the commercial market.

Elimination &Health Rights &Migration Bill Brieger | 13 Apr 2013

Malaria Elimination in a Challenging Human Rights Environment

A new article by Wickramage and Galappaththy raises numerous challenges facing a country like Sri Lanka that is approaching malaria elimination.  Human trafficking takes people from a malaria free zone, transits them through malarious areas in West Africa, and then in this case they are rescued and returned home, some carrying malaria parasites.

the-spatial-limits-of-malaria-transmission-maps-in-sri-lanka-2010-sm.jpgOther island nations are also addressing the problem of preventing future reintroduction of malaria, but they are not in a post-conflict situation that creates what Wickramage and Galappaththy euphemistically called “irregular migrants.” Seychelles has addressed both vector control as well as provision of malaria chemoprophylaxis and health education to outbound citizens.

Trafficked citizens would obviously and unfortunately miss the opportunity to get prophylaxis (as well as many other opportunities in life).  In Sri Lanka those returning from trafficking transit in West Africa were screened at the airport and treated. Seychelles could learn from this experience.

Mauritius has not had an indigenous malaria case in over a decade although the vectors are still present. Mauritius actively screens people return from malaria endemic areas at both airport and seaport.

Malaria Journal reports that in Sao Tome and Principe “A steep decline of ca. 95% of malaria morbidity and mortality was observed between 2004 and 2008 with use of the combined control methods. Malaria incidence was 2.0%, 1.5%, and 3.0% for 2007, 2008, and 2009, respectively. In April 2008, a cross-sectional country-wide surveillance showed malaria prevalence of 3.5%, of which 95% cases were asymptomatic carriers.”

So yes, countries approaching elimination must have a surveillance system that finds both obvious clinical cases as well as asymptomatic infections among residents and people returning to or visiting from the outside.  Island nations are among the first to put this process to the test.  But the bigger lesson from Sri Lanka’s ‘irregular migrants’ is that as long as conflicts, human trafficking and human rights violations persist, malaria will be difficult to eliminate.  Malaria demonstrates that no man or woman is an island.