Think of the most improbable miniature helicopter of all, or those unbearable ‘drum beats’ in your ear. You gotcha the whole idea right — a hazard you’d not even touch with a perch pole, as it were. Now, to the basics. With her brittle body, and spiky arsenal of wings, legs and antennae poking out in every possible direction, the perilous mosquito is making a travesty of our scientific and technological progress. This isn’t all. The dangerous insect, with her aggro image, is, indeed, the ‘femme fatale,’ in more ways than one. She enacts a biting tale of paramount importance, with more than an element of computerised consistency. Her message is simple — sucking blood to proliferate her race.
As she scans her sphere for a possible target, her wings beat from 250 to 500 times a second. Rainfall, heat, or dust, cannot affect her movements; in fact, nothing can, except the latest repellent, or the more advanced spray, up until she overcomes its remedial strength with her indigenous dexterity and sublime craft. Not only that. The female mosquito can switch off her incredible wing muscles in her midsection, while enabling them to relax and contract as quickly. Interestingly, her sense of sudden attack or blitzkrieg is variable. If some of the 2,800 mosquito species, we now know of, bite only during daytime, others revel in their activity at dusk — especially when it is quietly dark.
That she cannot see in the dark is no problem — the night-biting mosquito uses her sensors, two antennae and three pairs of legs — to find for herself a grand snack She catches the scent of your exhaled carbon dioxide, and gets closer to determine whether you are ‘sport’ to her gastronomic instincts. Smart, and practical creature that she is, a mosquito is often in the family way — having mated already — much before she has ‘pinched’ her first blood nibble.
The mosquito has a volatile functionality. One mosquito bite, for example, can inject up to 600 malaria sporozoites, or the motile infective form of the malaria parasite: each one of them yielding up to 30,000 ‘daughters.’ While the males of all species — and, females of several species — survive primarily on the nectar of flowers and also play an important role in pollination, some prefer the bloodstream of elephants and mice too — not just human beings. A species, in Africa, for instance, preys only on ants, drawing from its mouth honey, not blood. Another species bites turtles through their shell — that is through the animal’s solid armour.
Mosquitoes, tiny as they are, have destroyed civilisations. Science testifies that they may have contributed to the decline of ancient Greece and Rome. Even today, the devastation of mosquito-borne diseases continues: primarily in the form of malaria, yellow and dengue fevers, and filariasis, otherwise called elephantiasis. In the times we now live in, the mosquito has rocked several regions of Asia, Africa and South America. Its treacherous effects, aside from that “small, high, hateful bugle” in your ear as author D H Lawrence put it in purple prose, have returned to rattle the US too, with a settling of scores.
Malaria [mal’aria = bad air] has been a relentless peril since historic times. In ancient Egypt, malaria occurred mainly in lowland areas. The testimony: enlarged spleen, the organ, which is the illness’s ‘refuge,’ of some Egyptian mummies. The illness has also claimed several illustrious victims, down the ages. To name a few: Alexander the Great, in June 323 BC; Pope Innocent III, in 1216; Dante Alighieri, the great poet, in 1321; Raphael Sanzio, the legendary artist, in 1520; and, Oliver Cromwell, in 1658 — to name a few.
Malaria is a complicated and deadly infection — in factual terms, it is actually four illnesses, caused by four related parasites, each having distinctive characteristics: Plasmodium falciparum, P vivax, P ovale, and P malariae. The bite of a female mosquito of the genus anopheles transmits the infection to people during the process. The illness is obviously a big target of intense international efforts employing some of the most advanced techniques available at the frontiers of modern science and medicine in an attempt to discover new weapons for fighting an old, dangerous enemy. All the same, the illness continues to claim over a million lives in the tropics alone on an annual basis.
Malarial patterns, in India, are manifold. Though the government spends a major chunk of its entire healthcare budget on malaria control, there has been no let-up in outbreaks of the illness. For several reasons — most notably, the ineffectiveness of DDT and other insecticides, chloroquine’s losing battle with its potency, besides bad environmental hygiene.
What’s more, modern medicine, despite making significant progress against the parasite in the 1940s and 1950s, seems to have also run out of ideas due to new resistant strains. No wonder why the illness is now felling victims in over 100 countries, most of them children. The African countries where 90 per cent of malarial deaths occur have been ravaged by hostilities, no less, making it all the more difficult to combat the scourge. Worse still, developed nations, especially the US, that used to earlier fund most of the malaria research, are limiting, or even cutting their budgets.
According to a report published by the Institute of Medicine [IoM], US, scientists have a long way to go in deciphering malaria’s basic biology. It is not known, for instance, why some people living in malarial areas become violently ill, while others develop immunity. True, the IoM study had to go through a difficult path: of competing camps, basic researchers, clinicians and mosquito-control experts. In the end, the panel did not single out any particular strategy for attention, but instead proposed one, which embraced them all. Here’s a short checklist of the specifics: reorient massive screening programmes; collect data, focused on high risk groups and potential epidemics on the basis of scientific merit, rigorous peer review and co-ordination. The IoM report is not without its critics. As one of its authors explained, “There is too much emphasis in this study on malaria research, while little attention is given to malaria prevention and control.”
Malaria is commonplace in most tropical and subtropical countries; it is also a serious and sometimes fatal illness. There is no vaccination available against it; however, you can protect yourself by avoiding bites, because mosquitoes cause much inconvenience owing to local reactions to the bites themselves, and from the infections they transmit Mosquitoes also spread Japanese-B encephalitis, besides malaria.
Practical measures emphasise on the avoidance of mosquito bites, especially after sunset. Wearing long-sleeved clothing and long trousers at night is ideal. Mosquitoes often bite through thin clothing; you may, therefore, spray or apply a repellent on your clothing, and, of course, on exposed skin. Repellents may be sprayed in the room, or you can burn coils [some researchers question its safety in the light of reports suggesting that coils and other newer products may be carcinogenic] and/or use heated insecticide-impregnated tablets to control mosquitoes. When you sleep in an unscreened room, or outdoors, the best thing to do is to use a mosquito net. There are easy-to-carry, lightweight nets available. All the same, contrary to popular belief, garlic, vitamin B and ultrasound devices, or certain plants, do not prevent mosquito bites.
If you intend to travel, you need to take anti-malarial tablets, which your doctor can prescribe, three weeks before departure. You ought to take the tablets regularly, preferably during, or after, a meal. Physicians and therapists also advise that you continue taking the tablets for four weeks after you have returned. This is suggested to cover the incubation period of the illness. Some medications require short post-travel-return treatment — of just about a week. There are some effective complementary and alternative medicines and herbs available to help you beat the malarial threat and complications, albeit their precise nature of action, or effect, is not established. Speak to a complementary physician or therapist to know your options better. However, any which way you look at it, preventive measures do not offer one hundred per cent guarantee of protection. Yet, they are useful. However, if you are subject to malarial, or any other infectious, fever between one week after first exposure, and up to two years following your return, it is ideal to seek professional, or specialist, advice — more so, if you had travelled to a malaria, or malaria-prone, area.
Well, the point is simple — for any preventive step to work, it should interrupt the life-cycle of the parasite, especially at the egg-laying phase when stagnant water becomes essential to the mosquito. This is the trickiest part. One new method, however, has been encouraging: the bio-environmental strategy, which employs fish, like guppy, to eat the mosquito larvae. The idea has paid dividends in the mosquito density and malaria areas of UP, Gujarat and Pondicherry. Yet another [high-tech] methodology which has excited scientists is a polymeric vaccine developed by the Columbian biochemist, Manuel Patarroya, among a few new vaccines. As Nature explained, “The degree of protection is not dramatic, but it is the first time that such a [large] trial has been undertaken and, indeed, a certain degree of protection was achieved.” Certain degree isn’t full degree yet. New, in-progress research expects new vaccines that are in use, or on the anvil, to be the touchstone in the future development of malaria prevention. This includes a multi-stage vaccine that would be capable of attacking the parasite at different stages of its life-cycle. If everything goes well — and, the potent weapon does achieve its full potential, we will have a good reason to celebrate a huge victory in one of mankind’s longest battles of attrition ever fought in history.
Wait a minute. There is some good news — combination therapies based on artemisinin, derived from the sweet wormwood plant, and given over three days, are reportedly ‘95 per cent effective’ in curing malaria. A pharmaceutical major has developed artemisinin as the basis for artemetherlume-fantrine [Coartem] — a combination drug that squashes the plasmodium parasite. It has been reported to be as effective against resistant strains. As a matter of fact, thanks to the efficacy of the drug, the World Health Organisation [WHO] has now included Coartem on its list of essential malaria medicines. This has given the impetus for many of the developing nations to declare the drug as their ‘primary line’ of treatment for malaria.
There is also a downside. The annual demand for artemisinin is estimated to be 80 million doses — this is a quantum jump from 200,000 doses originally envisaged. The plant is grown mostly in China and Africa. Suppliers are unable to cope with the huge demand, although Coartem is not expensive in terms of Western standards; it costs about US$3.00. It is supposedly expensive in the developing world. According to Jay Keasling, who specialises in the chemistry of isoprenoids, a family of about 25,000 chemical compounds that include precursors of plant products used to make medicines, such as the anti-cancer agent, taxol, from yew trees, there is a substitute to the costly and laborious process of isolating natural elements from harvested plants. This was exactly what that has prompted him to turn Escherichia coli into an artemisinin industrial unit. More recently, the world's first malaria vaccine received the green signal from drug regulators. The shot, called RTS,S or Mosquirix, is, in effect, the first licensed human vaccine against a parasitic disease. It is suggested to help prevent millions of cases of malaria in countries that would use it, albeit malaria specialists have expressed concern that the complexities and potential costs of employing the first vaccine when it provides but partial protection. This they also aver would make it less attractive and also dicey.
So, there we are — so near and yet so far in our battle against malaria. The best thing to do is conventional wisdom — the good, old adage of prevention is better than cure — without waiting for a miracle malaria cure to emerge soon.