The big bite4 min read . Updated: 23 Sep 2010, 07:33 PM IST
The big bite
The research facility at the Dabur India Ltd factory in Ghaziabad, UP, has a group of chambers that once saw painstaking analysis of the death of a mosquito.
The main chamber contains glass cubicles of different sizes lit by stark fluorescent lights. The cubicles, the largest measuring about 20x10ft, are representations of an average “living area". They flank another room, laid out like a museum exhibit, containing rows of tanks where mosquitoes are bred.
Large groups (400-500 at a time) of the insects were let into these cubicles through a tiny hatch on the side, and a mosquito coil was lit in its centre.
“Every inch of the cubicle floor used to be electronically wired, so we had a counter that went up every time a mosquito dropped dead," says S.V. Devasthale, the head of the facility. Scientists would stand outside the cubicle and take notes, comparing the efficacy of the coil’s careful mix of Allethrin-based insecticide.
Dabur exited the mosquito coil business a few years ago to focus solely on its Odomos range of mosquito repellent creams. The creams work by cloaking the body’s potent odour mix of carbon dioxide and lactic acid that mosquitoes, otherwise blind, hone in on. The chambers now feature tests where scientists watch mosquitoes hovering around subjects smeared with the cream.
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Mosquitoes are the focal point of an enormous amount of research in India. Apart from corporate labs that develop consumer products—an industry estimated at around ₹ ,300 crore—organizations such as the National Institute of Malaria Research (NIMR) and the Indian Council of Medical Research (ICMR) are active in this field.
“There’s so much to be done," says T. Adak, a scientist at NIMR, “from testing field applications of new insecticides and developing drugs to monitoring behavioural patterns and adaptations."
The rationale and the figures are stark—a million deaths a year from malaria worldwide and dengue outbreaks in around 20 countries this year. Medical facilities in the event of an outbreak are stretched to capacity, and the availability of drugs wavers from uncertain to adequate.
“The use of coils and repellents is only a temporary solution," says Dr Adak. The biggest impact, he says, comes from what is called “residual spraying", which involves the use of fogging machines and large-scale operations to wipe out mosquito-breeding spots. “These (residual sprays) are semi-permanent solutions, needing repeated applications every six months or so."
The problem with residual spraying, however, is evidence of mosquitoes developing resistance to insecticides. “Mosquitoes have already developed resistance to early, first-generation pesticides like DDT, making them less effective," says Dr Adak. They now seem to be resistant to even newer forms of pesticides, such as the petroleum-based synthetic pyrethroids. “These are part of a group of chemicals used in agriculture, and mosquitoes are exposed to it right from the larval to the adult stage," Dr Adak says. “The possibility of developing resistance, therefore, is higher."
So far, there’s no data to suggest that mosquitoes are resistant to the repellents and coils used in homes. “Their exposure to it is very brief, and it will take much longer for them to adapt to it," says Dr Adak.
The NIMR is now working on field applications of what it calls “impregnated mosquito nets". These are nets embedded with new, third-generation insecticides. “Mosquitoes that come in contact with them die within 30 seconds, and these nets are very long-lasting, up to four-five years," Dr Adak says.
On the consumer side, mosquito coils (such as the old favourite Tortoise—a brand now owned by Bayer Healthcare) account for about ₹ 1,100 crore, or half the total market of mosquito repellent products. Concerns about safety and long-term exposure to coil smoke haven’t diminished the market’s growth. Agrees Tarun Arora, executive vice-president of marketing and sales at Godrej Sara Lee, which sells the rival Good Knight range of mosquito products, “We’ve seen annualized growth of about 10%, with last year seeing about 28%."
The market is also seeing new entrants such as Camlin Ltd (makers of stationery) and Eveready Industries India Ltd (makers of batteries). Each year also sees a new device of dubious origin flood the grey market, from the shrill high-pitch “ultrasound" noise emitters of 2008 to the tennis racquet electrocution devices of last year. Korea’s SK Telecom recently introduced a mosquito repellent “app" for mobile phones that drives away mosquitoes by recreating the “buzz of a male mosquito, which females tend to avoid".
Dabur claims the market for mosquito creams, estimated at ₹ 40 crore, grew 40% year-on-year in the first quarter of 2010, with the current quarter poised to be “even better".
“What’s happened over the last few years is that these products have moved from being therapeutic to day-to-day," says Rohit Prakash Gupta, category head, home care, for Dabur consumer products. “We’re seeing about 60% of our sales from grocery shops and less from medical stores. It used to be the reverse." Keeping up with the times, the creams are now available in a variety of form factors—from sprays and lotions to gels and aloe vera-infused moisturizers.
Despite everything, however, the basic chemical constituent of the cream (a central active ingredient called N, N-diethylbenzamide, a pale yellow liquid that smells like curd) has not changed since the 1970s. “We essentially work to make it more consumer-friendly," says Dr Devasthale. “People used to say that if you want to drive away your husband or wife, use lots of Odomos."