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Archive for "Vector Control"



Vector Control Bill Brieger | 06 Apr 2014

Vexing Vector Visualizations on World Health Day

small bite big threatThis year World Health Day (April 7th) focuses on insect vectors of disease with the theme “small bite, big threat.” WHO explains that, “Mosquitoes, flies, ticks and bugs may be a threat to your health – and that of your family – at home and when travelling. This is the message of this year’s World Health Day.” Furthermore “Every year, more than 1 billion people are infected and more than 1 million die from vector-borne diseases.”

Wrong mosquito used in article about malaria

Wrong mosquito used in article about malaria

While we are happy about this world-wide attention to disease vectors in general, at Malaria Matters we are particularly concerned with the various anopheles mosquitoes that carry malaria parasites. Thus it is time to vent a little frustration with the media that visually sends the wrong message about mosquitoes and malaria.

First we can see a typical news story on our first screen shot that presents an article about malaria with a photo of Aedes aeqypti mosquitoes that carry dengue and yellow fever.  While one can agree that this black and white striped mosquito is a bit scarier and attention grabbing than a blander colored anopheles, it still gives wrong information and wrong ideas. The two mosquitoes have very different biting and breeding and patterns that lead to very different control interventions.

Mosquitoes_Page_01Granted, the general public might not distinguish among the various nuisances called mosquitoes, but at least professionals aiming to communicate information about malaria should research and present the correct graphics.  Fortunately we can rely on the US Centers for Disease Control and Prevention to help us distinguish our mosquitoes.

Another concern with the media is a stress on malaria control interventions that may not be the major focus of key international programs that are part of the Roll Back Malaria (RBM) Partnership.  RBM and partners set sights on three main malaria interventions at the onset – insecticide treated bed nets (ITNs), prompt and appropriate malaria case management, and intermittent preventive treatment (IPT) for pregnant women. WHO offers guidance on each of these interventions that donors like the Global Fund and the US President’s Malaria Initiative follow in making their funding decisions.

Malaria control has expanded cautiously from the three core interventions to include indoor residual spraying (IRS) in epidemiologically appropriate settings. Larviciding under restricted conditions is now included to round out an integrated vector control strategy. Also the concept of IPT was tested with infants and children and has now become the strategy of seasonal malaria chemoprevention (SMC) in countries of the Sahel. These additions have come after rigorous scientific testing and with an eye to the economic costs and benefits of supporting scale up.

Outdoor fogging is not a RBM malaria control strategy

Outdoor fogging is not a RBM malaria control strategy

Ironically, some media outlets and city councils get fixated on outdoor spraying or fogging (as seen in photo). This is NOT a RBM strategic intervention for a number of reasons. INDOOR residual spraying is designed specifically with the behavior of anopheles in mind because they do rest on the walls inside houses after biting and residual means the insecticidal effect lasts for some months. OUTDOOR fogging is hit and miss and dissipates.

So in conclusion we hope people will use today’s World Health Day focus on vector borne diseases to give a nod to the Pan-African Mosquito Control Association and to get to know their mosquitoes and mosquito interventions better.

IRS &Vector Control Bill Brieger | 15 Oct 2013

Impact of Indoor Residual Spraying on the Parity rate of Anopheles mosquitoes in Nasarawa State, North Central Nigeria

Picture3 aInyama, P.U., Samdi, L., Nsa, H., Iwuchukwu, N. Suleiman, H., Kolyada, L.,  Dengela, D., Lucas, B., Seyoum, A. and Fornadel, C. Are associated with the PMI/AIRS Project in Nigeria. They presented their experiences with IRS at the recently concluded Multilateral Initiative for Malaria 6th Pan African Malaria Conference in Durban South Africa.  They have shared their presentation here.

The President’s Malaria Initiative’s Africa Indoor Residual project (PMI/AIRS), IRS 2 Task Order 4, executed the year 2 spray operation in Nasarawa Eggon and Doma Local Government Areas (LGA) of Nasarawa State, Nigeria. The objectives of the program being the reduction of malaria – associated morbidity and mortality, a total of 62,592 structures were sprayed.  To measure the impact of the IRS program on the malaria vectors  the proportion of parous mosquitoes in  the  vector population  was determined before and after Indoor Residual Spraying.

Picture1 aOne thousand, six hundred and twenty one (1,621) female Anopheles gambiae s.l. specimens drawn from a pool of 3,356  Female Anopheline   mosquitoes  captured by Human Landing Catches  from  three LGAs of Nassarawa Eggon and Doma (intervention areas)  and Lafia (Control) of Nasarawa State Nigeria    were dissected using WHO-recommended techniques for parity. The degree of coiling of ovarian tracheoles was observed  pre-IRS intervention in March 2013  and monthly post IRS intervention up to September 2013. Proportion of parous females was compared pre-and between intervention and control villages. Similarly, pre-and post-spray proportion of parous comparison was made within both intervention and control villages.

Picture2 aOverall, a total of 1,621 ovaries of An. gambiae s.l. were dissected before and after IRS intervention.  Of the ovaries dissected at baseline, 71.43% were parous in Nassarawa Eggon, 76.70% in Doma and 77% in the control area. After IRS in May 2013, it was found that the parity had declined dramatically to 17.69% in Nassarawa Eggon, 27.98% in Doma (p <0.05) while in the control area (Lafia) Parity remained as high as 68%. As insecticide residual efficacy continued to decline, slight increase in parity rate was observed in the intervention areas (38% and 31% in N/Eggon and Doma respectively for September) while it remained high (71%) in the control area for the same month.

spraying 2This study has shown a reduction in the longevity of Anopheles mosquitoes post spraying as compared to pre-spraying in the intervention villages.   The longevity of the vector was also significantly declined post spraying in the intervention villages as compared to unsprayed villages. The observed reduction of the expectation of life of the vector associated with IRS is promising. But further study is needed to fully understand how this will be translated to reduction of malaria transmission in the area.

spraying 3We wish to thank all technicians who participated in the entomological surveillance activities and dissection of mosquitoes. This work was funded by the President’s Malaria Initiative. www.africairs.net and info@africairs.net

Vector Control Bill Brieger | 10 Oct 2013

Launching PAMCA: MALARIA ELIMINATION IMPOSSIBLE TO ACHIEVE WITHOUT AFRICAN ENTOMOLOGISTS

MALARIA ELIMINATION IMPOSSIBLE TO ACHIEVE WITHOUT AFRICAN ENTOMOLOGISTS

MIM2013 Pan African Malaria Conference, Durban, South Africa – 16:30 pm 10 October 2013

pamca logoMajor success in the fight against malaria has largely been due to efforts aimed at killing mosquitoes. The targeted attack has involved deployment of bed nets and indoor sprays that include insecticides. But mosquitoes are developing resistance to these chemicals while at the same time global funds for their deployment are shrinking. In the push towards global elimination of malaria, we need to get smarter in the way we wage war against our six-legged enemy.

Entomologists are those intimately associated with the whereabouts and happenings of mosquitoes. They spend hundreds – if not thousands – of hours trekking through muddy villages, inspecting watery holes for young mosquito larvae, and collecting mosquitoes resting on walls of huts. Basic tests for the killing power of insecticides are performed in make-shift field laboratories in hotel rooms or even converted shipping containers. Essential information on mosquito behavior guides which anti-mosquito tools to use where, and at what time. It can be the difference between choosing a tool that will have high impact or no impact, decision which can amount to millions of dollars and thousands of lives. The expertise of entomologists is critical in guiding anti-malaria efforts.

Yet there is a dire shortage of entomologists worldwide and across Africa. Some high-burden African countries have less than a handful of expert entomologists. Very few African countries have entomology programmes at undergraduate university level. Specializing at a higher level is impossible without guidance from an experienced mentor, of which there are precious few.

The new Pan-African Mosquito Control Association brings together members of this elite yet endangered group from across the continent. As a united group, they will provide leadership and training to the next generation of entomologists. Efforts also focus on providing critical technical support as countries refine their malaria elimination strategies. Together they issue a sustained call for increased investment in this critical area.

The successful launch of PAMCA will be celebrated at the 6th Pan-African Malaria Conference held in Durban this week. The celebration will be graced by the Goodwill Ambassador for the Roll Back Malaria Partnership, Ms Yvonne Chaka Chaka. Over 50 renowned entomologists from Africa and beyond are expected to attend.

“This initiative is thoroughly welcome. We cannot relent in the fight against malaria – and African entomologist are our best weapon“, said Ms Chaka Chaka. “It will be impossible to say goodbye to malaria for good without their expert help”.

Those equally engaged in the fight against mosquitoes but unable to attend the launch celebrations are urged to join the cause via www.pamca.org.

For more information, please contact PAMCA Communications:
Tessa Knox
Tel:    +254 733 433 392
Email: tessaknox@hotmail.com
communications@pamca.org

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.

Vector Control Bill Brieger | 04 Dec 2012

Geographical factors affecting the implementation of alternative strategies for lymphatic filariasis elimination in post-conflict countries

Lymphatic filariasis, like malaria, is a mosquito-born disease. Below, Michelle C. Stanton, Moses J. Bockarie and Louise A. Kelly-Hope of the Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, share an abstract of their study on vector control for lymphatic filariasis. Michelle was one of the candidates for the Young Investigators’ Award at the 2012 American Society for Tropical Medicine and Hygiene meeting in Atlanta.

cntd-banner-sm.jpgAbstract

Vector control, including the use of bed nets, is recommended as a possible strategy for eliminating lymphatic filariasis (LF) in post-conflict countries such as the Democratic Republic of Congo (DRC).

This study examined the geographical factors that influence community bed net coverage in DRC in order to identify the hard-to-reach areas that need to be better targeted. In particular, urban/rural differences and the influence of population density, proximity to cities and health facilities, plus access to major transport networks were investigated.

Demographic and Health Survey geo-referenced cluster data were used to map the proportion of households with at least one bed net (unspecified), with at least one insecticide-treated net (ITN) and ITNs per person for 300 communities. Spatial statistical methods and bivariate and multiple logistic regression analyses were used to determine significant relationships.

Overall, bed net (30%) and ITN (9%) coverage were very low with significant differences found between urban and rural communities. In rural communities coverage was significantly positively correlated with population density (p<0.01), and negatively with the distance to the two largest cities, Kinshasa or Lubumbashi (p<0.0001). Further, coverage was significant negatively correlated with the distance to primary national roads and railways (all bed net measures), distance to the main river (unspecified only) and the distance to the nearest health facility (ITNs only).

Logistic and Poisson regression models fitted to the rural community data indicated that, after controlling for the effects of the measured covariates, coverage levels in the Bas-Congo province close to Kinshasa were much larger than expected. This was most noticeable when considering ITNs and ITN density which were 5.1 times higher in the Bas-Congo province compared to all other provinces.

These maps and spatial analyses provide key insights into the barriers of bed net coverage, which will help inform both LF and malaria bed net distribution campaigns as part an integrated vector management (IVM) strategy.

Elimination &Vector Control Bill Brieger | 29 Sep 2012

The Role of Malaria Prevention and Vector Control in Rwanda’s Progress toward Malaria Elimination

A second working group at the recently completed First Rwanda Malaria Forum examined issues around “Malaria Prevention and Vector Control.” A key message from the Forum was the need to protect existing vector control technologies (IRS and LLINs) and well as develop and test new ones in the local setting. These can be deployed in a focused manner as better entomological and epidemiological data are available on district, sub-district and cross-border areas.

dscn7129asm.jpgMembers of the group included – Hakizimana Emmanuel, MOPDD-Rwanda; Abraham Mnzava, WHO/HQ; Beata Nukorugwiro, JHPIEGO; Cait Unites, PSI; Beatus Cyubahiro, RBC-MOPDD; Dunia Mwuyakango, RBC-MOPDD; David Wainaina, Bayer; Arielle Mancuso, PMI/RFHP; Moses Turyazooka, CREST Technologies; Richmond Ato Selby, Networks; Christine Ochieng, Vestergaard Frandsen; Tessa  Knox, Vestergaard Frandsen; Levin Nsabiyumva, USAID/Burundi; Kagabo Jean Bosco, World Vision Rwanda; Athanase Munyaneza, RBC/KFHIK; Duschuze Clemence, RBC/MOPDD; Sangala Freddy, Nyagatare Hospital; John Githure, MOPDD/RBC; Francisco Saute, USAID/PMI

The group suggested the following Strategic Objectives to be achieved by or before 2017 …

  1. Generate local evidence to guide optimization and diversification of available vector control interventions
  2. Build sustainable capacity for entomological  monitoring and vector control at national, district and community levels
  3. Formulate policies and procedures for effective and sustainable mobilization of vector control activities
  4. 90% of the population at risk of malaria will have access to locally appropriate vector control  interventions based on evidence
  5. Establish harmonized mechanism for cross border collaboration on vector control interventions

Key Actions For Strategy 1:

  • Establish a national entomological profile (vector ecology and behavior, species composition and distribution, susceptibility to insecticides)
  • Re-enforce and expand entomological  surveillance sentinel sites
  • Determine the appropriateness of vector control interventions – including new tools
  • Conduct operational research on the effectiveness of vector control interventions

Key Actions for Strategy 2:

  • Recruit and train entomologists for deployment at district level for vector control interventions and entomological surveillance
  • Strengthen and expand field lab/insectary facilities for entomological monitoring at sentinel sites
  • Collaborate with the existing Dept. of Environmental Health at the KHI to include medical entomology programme
  • Empower the communities through training on vector control

Key Actions for Strategy 3:

  • Develop insecticide resistance management plan
  • Establish regulatory processes to support timely deployment of existing and new tools as they become available
  • Develop a transition plan for decentralization of vector control activities
  • Re-orient IEC/BCC strategy to better support pre-elimination efforts
  • Evaluate human and other factors influencing the effective lifespan and acceptability of vector control tools

Key Actions for Strategy 4:

  • Maintain universal coverage with LLINs in the population at  risk
  • Rational deployment of IRS in prioritized risk areas
  • Evidence-based deployment of other supplementary vector control interventions (e.g. repellents, screening, LSM) where appropriate

Recommendations

  • Establish a national inter-sectoral steering coordination mechanism for planning and implementation of  integrated vector management (IVM)
  • Enhance entomological capacity in moving towards pre-elimination phase
  • Integrate vector control within district development plans and operational targets
  • Long term financial commitment of Government of Rwanda and development partners is essential to achieve and sustain the gains in malaria prevention

Private Sector &Vector Control Bill Brieger | 08 Aug 2011

A goldmine of private sector assistance against malaria

Guest Posting by Emmanuel Fiagbey, Voices, Ghana, August 4, 2011: Sefwi Etwebo, Western Region of Ghana

Chirano Gold Mines Ltd. just launched a $5.6 million Integrated Malaria Control Program and joined the United Against Malaria Partnership. Private sector involvement in malaria control has received a big boost in Ghana with the launching of a $5.6 million malaria control program by the Chirano Gold Mines Ltd, a Kinross Company. Over 600 people including chiefs, queen mothers, government officials, mine workers and the people of the Sefwi Wiawso and Bibiani Anhwiaso Bekwai District attended the lively durbar which marked the occasion.

chirano-goldmines-local-chiefs-at-launching-sm.jpgA section of the chiefs and community members who attended the launching are pictured to the right.

“Malaria is a killer, it is the largest cause of death in the Sefwi area. With this effort directed at improving prevention and treatment, this insidious malaria cycle can be reduced and broken. Reducing the impact of this disease on our workforce, the surrounding communities and the socio-economic structure is our goal.” So says Mr. John Seaward, General Manager of the Chirano Gold Mines, speaking at the launch ceremony.

Developed and modeled on the highly successful integrated malaria control program of Anglo Gold Ashanti, the Chirano Gold Mines program extends over 13 communities within and outside the operational area of the Chirano Mines.

The first phase of the program which began in September, 2008 as a Mosquito Abatement Project with a major focus on larval control and environmental management grew into a fully integrated program in May 2009 and the results so far are astounding. At the Chirano Mines Clinic, the incidence of malaria has reduced from 912 treated cases per 1000 in 2008 to 210 cases per 1000 people this year 2011 amounting to a reduction of 77% in four years.

chirano-general-manager-sm.jpgThe General Manager (photo at left) hinted that after a successful implementation of the first phase of the project (2008-2011) and sustaining the level of achievement being made, the interventions will be intensified and extended to cover 50% of the communities in the two districts through 2016.  Implementation activities would therefore focus on vector control measures such as IRS, targeted larviciding and the distribution of LLINs supported with engagement of community leaders and people in prevention and treatment community education activities.

A representative of the Manager of the National Malaria Control Program, James Frimpong commended the efforts of Chirano Gold Mines in supplementing the country’s efforts at working towards eliminating malaria from Ghana. He promised the NMCP’s continued support for the Chirano Gold Mines Integrated Malaria Control Program. Also present at the event was the World Health Organisation Malaria Program Adviser Dr. Felicia Owusu-Antwi.

The UAM partnership was not left out of this event. Mr. Emmanuel Fiagbey, Country Director of the JHU CCP Voices project presented a UAM Ball and 10 copies each of the UAM Malaria-Safe Playbook and CDs of the Black Stars Malaria Cheer song to the General Manager, Mr. John Seaward and invited Chirano Mines to the fold of the UAM partnership. “The UAM Black Stars Cheer Song will not only provide messages on prevention and treatment but also help in mobilizing community members to actively participate in the program’s community level educational activities,” Mr. Fiagbey stressed. The UAM Malaria Safe Plabook provides guidance to Private Sector companies on ways in which they could sustain their malaria control activities applying the four pillars of Education, Protection, Visibility and Advocacy.

In his response Mr. Seaward who was moved by the presentation remarked, “I am humbled by the fact that the Ghana Black Stars are also part of the campaign against malaria”. “We at Chirano Mines are pleased that our efforts are being recognized and are ready to work with all others to ensure the malaria cycle is broken. Malaria can be eliminated and Ghana can be malaria free,” he declared.

Other partners on the Chirano Gold Mines Integrated Malaria Control Program include the Vector Control Consult Ltd (Principal Implementer), the Noguchi Memorial Institute of Medical Research, the District Assemblies of Sefwi Wiawso and Bibiani Anhwiaso-Bekwai and their District Health Management Teams and the Ghana Education Service.

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