Mosquito: The Story of Mankind's Deadliest Foe

Mosquito: The Story of Mankind's Deadliest Foe by Andrew Spielman, Michael D'Antonio. Faber and Faber, £10.99, pp 248. ISBN 0 571 20980 7. Rating: ★★★

With climate change and increased international travel, mosquito borne illnesses are flaring up all over the globe. This book tells the story of some of the mosquito species that contribute to human diseases such as malaria, yellow fever, dengue fever, filariasis, and viral encephalitis.

One such species is Culex pipiens, which lives in towns and cities rather than swamps and which caused the epidemic of West Nile viral encephalitis in New York city in 1999. How did a mosquito borne virus from Africa get to America? The authors are dismissive of terrorism or an African tourist as the explanation, but blame either the illegal trade in birds or aircraft stowaway mosquitoes. It is one more example of the deadly consequences of diseases with no borders, when encounters occur between endemic mosquito borne infections of one region and non-immunes from another.

Culex pipiens was also implicated in an outbreak of Rift Valley virus in Egypt in the late 1970s. This outbreak was caused by simultaneous infection of mosquitoes by virus and microfilariae, which wounded the mosquito's gut and allowed virus to penetrate its saliva, leading to human Rift Valley viral infections. This important observation meant that other Mediterranean countries with this mosquito but without filariasis were not at risk of Rift Valley virus outbreaks.

Readers from “down under” may be disappointed to find no mention of Kunjun and Murray Valley encephalitides, although Ross River virus does rate a mention. But one of the strengths of this book is its selectivity. Spielman has been a key worker in research into mosquito borne disease, and so brings a unique perspective to the story, which is told well for a non-medical audience.

The brief history of yellow fever research in Latin America in the 1880s underlines just how much research ethics and methodology have changed. Perhaps researchers battling fastidious research ethics and grant committees will be interested to know that back then, mosquitoes which had bitten yellow fever victims were allowed to feed on healthy subjects in unblinded uncontrolled experiments. It is also the story of individual researchers and their idiosyncrasies and egos. Plus ça change . . .

What practical advice can be offered to travellers to avoid these mosquito borne diseases? The best protection is wearing appropriate clothing and a repellent based on DEET (N,N-diethyl-meta-toluamide) when going outdoors. According to the authors, electronic zappers and ultrasonic repellents are ineffective, but permethrin impregnated bednets are effective.

In view of the increasing resistance to insecticides and chemotherapy, perhaps the greatest promise to ending mosquitoes' deadly assault on man is to render them impotent by genetic manipulation. As for genetically modified food, however, there are still unanswered questions about the advisability of this approach. More to the point, what chance is there that antiglobalisation and ecology activists will accept a genetically modified mosquito? Perhaps the major challenge for health research this century will not be so much any actual advances in molecular biology as convincing an increasingly sceptical public of their benefits.