Yaounde Initiative Foundation» Graham Matthews

YIF is assessing a cold fogger for adult mosquito control

Graham Matthews — Thu, 07 Jun 2018 12:56:48 +0000

There is a new addition to the YIF toolbox for vector control – a vehicle mounted cold fogger has been imported from the UK for trials to determine whether a routine space treatment can drastically reduce a mosquito population and thus protect people from outdoor biting and malaria transmission in urban areas. The research complements extensive field trials carried by YIF on slow release pesticides for Indoor Residual Spraying (IRS). This photo is from the United States where space spraying for adult mosquito control is widespread.

New publication on the impact of distributing insecticide treated mosquito nets

Graham Matthews — Fri, 30 Jun 2017 14:14:03 +0000

YIF assessed the impact of distributing 5,000 insecticide treated bed nets (PermaNets) and has published the results in Outlooks on Pest Management – see the publication at: https://bit.ly/2sUoobQ. The distribution of the nets had a substantial impact on malaria incidence in Libamba community, lasting for at least 4 years post-intervention.

Dr Jane Che was able to follow the incidence of malaria which showed that children benefited by being under the nets, but adults still got malaria. As a result of the expansion of electricity in towns and villages, people are not going indoors as soon as the sun goes down, so biting occurs during the evenings outdoors. However, it is quite clear from previous YIF research that effective control of malaria requires a ‘blended attack’, involving bednets, mosquito control, infection surveillance and awareness raising, rather than the one-technology approach that some promote. In The USA, space treatments are the main method of reducing mosquito populations, but so far WHO has only recommended cold or thermal fogs in emergencies such as at refugee camps.

Keeping the number of blackflies down

Graham Matthews — Mon, 21 Oct 2013 11:25:00 +0000

The Yaounde initiative has been continuing to treat parts of the Sanaga River between Edea and Monatele to keep the numbers of blackflies as low as possible while minimising the number of treatments of larvicide in the river. The data for 2012 and early 2013 show that where the river was treated the number of flies was generally below 50 blackflies per trap per day in contrast to upstream where the number of flies per trap were between 120 and 230 per trap per day. In 2012, the river was treated four times [starting 16^th March; 27^th April; 13^th; July, 9^thNovember] and twice in 2013 [starting 25^th January and 22^nd March] on the basis of action thesholds rather than calendar spraying. This frequency contrasts with the weekly spraying done during the 25 year Onchocerciasis Control Programme over most parts of west Africa.

Could odours be the solution to blackfly control?

Graham Matthews — Thu, 08 Dec 2011 16:35:36 +0000

The Yaounde Initiative Foundation has been carrying out field research in Cameroon in collaboration with the UK-based Natural Resources Institute (NRI) to see whether natural odours might be the key to cheaper and more environmentally safe blackfly control. Inaki Tirados of NRI and YIF staff put people and cattle into different tents, sucked out the odours, and measured how much they attracted blackflies. If the trials show a strong attraction, it might be possible to copy the Tsetse fly control method where insecticide is only sprayed onto targets, rather than sprayed over large areas, and the odours are used to attract blackflies to the targets. When the fly lands on a target it is killed.

Animated Guide to Indoor Residual Spraying

Graham Matthews — Thu, 03 Mar 2011 11:12:46 +0000

WHO published a short booklet on how to spray the inside of houses for mosquito control. An animated version of this booklet has been produced as a DVD and can be downloaded from

http://www.who.int/whopes/equipment/en/

You can click on either the pdf version of the booklet or the animated version below the text alongside a picture of the cover of the manual.

Update on blackfly control on the the Sanaga River

Graham Matthews — Thu, 03 Mar 2011 11:09:28 +0000

Many of the people who lived near the Sanaga River have moved out of the area due to the severity of the biting by blackflies (Simulium spp.). Those that remain have a high incidence of onchocerciasis (river blindness) and agricultural productivity is adversely affected by the constant biting of the flies.
The larvae of blackflies need highly oxygenated water found where there are natural rapids where the river is flowing over rocks, creating ‘white water’. A major source is where there are rapids such as near the village of Kikot. The problem of blackflies is also very severe near the hydro-electric dams as the spillways provide man made areas of ‘white water’.

YIF has been treating the river with a chemical to kill the larvae and this has significantly reduced the population of the flies. Instead of continuously treating the river upstream of these areas of ‘white water’ , the number of flies is monitored by placing plastic traps covered with glue on which flies land and become stuck, so that treatments are resumed only when the blackfly population has increased to a critical level.
After treatment blackfly larvae from upstream and smaller streams entering the Sanaga river mean that the number of flies biting people always increases after a treatment, but it is hoped that by treating areas further upstream the frequency of treatments can be decreased. Research is also needed into alternative methods of control.

New book on Integrated Vector Management in press

Graham Matthews — Wed, 02 Mar 2011 15:34:51 +0000

The most recent book by Professor Graham Matthews – YIF Technical Director – is entitled ‘Integrated Vector Management’ and is due to be published by Wiley-Blackwell mid-2011. It covers the use of different control techniques for insect vectors of human disease with chapters on the diseases transmitted by insect vectors, the types of insecticide, and application technologies. In particular, the use of indoor residual spraying (IRS), space treatments, larviciding and bednets. The primary focus is the integration of these technologies with non-chemical methods such as drainage of breeding sites and house improvements to prevent the entry of vectors.

Sanaga River blackfly control project continues

Graham Matthews — Wed, 01 Dec 2010 11:23:49 +0000

The Yaounde Initiative Foundation (YIF) is carrying out blackfly control on a part of the Sanaga River, funded by AES Sonel, an American/Cameroonian company which generates and distributes hydro-electricity in Cameroon. The numbers of blackflies have decreased from a very high level that was preventing workers carrying out their duties, and preventing rural populations farming and fishing, to almost zero.