Until CRISPR came along, biologists lacked the tools to force specific genetic changes across an entire population. But the system, which is essentially a molecular scalpel, makes it possible to alter or delete any sequence in a genome of billions of nucleotides. By placing it in an organism’s DNA, scientists can insure that the new gene will copy itself in every successive generation. A mutation that blocked the parasite responsible for malaria, for instance, could be engineered into a mosquito and passed down every time the mosquito reproduced. Each future generation would have more offspring with the trait until, at some point, the entire species would have it.
In Africa, every 2 minutes a child dies because of Malaria. The disease is most commonly transmitted by an infected female Anopheles mosquito.
MOMALA can diagnose malaria with higher accuracy and at a fraction of the cost of currently used solutions.
August 20th continues to be celebrated as Mosquito Day! On the 4 September he joined his family at Bangalore where he wrote a paper on his findings. This paper titled “On Some Peculiar Pigmented Cells Found in Two Mosquitoes Fed on Malarial Blood,” was published in the British Medical Journal on December 18, 1897.
Did his master thesis at MOMALA and supports the business development by doing market research in Kenya, attending networking events and basic marketing.
Yet Ross still had his doubts. Perhaps, circular cells might not be related to the malarial parasites at all. “I really believe the problem is solved,” he wrote to Manson, “although I don’t like to say so. I look at them myself daily; those of the fifth day have grown bigger than those of the fourth day….Pigment-it is almost proof already! What else can the thing be? What are we to think: What do you think?”
Unhappy with the administrative apathy and exhausted by work and heat, Ross decided to quit. He closed his small laboratory, set his feathered prisoners free from their cages, emptied the jars of mosquitoes. After sadly wishing Mohammed Bux good-bye, Ronald Ross left Calcutta on the 13th August, 1898. Before leaving, he urged upon Government the importance of taking active measures for the prevention of malaria in accordance with his observations. Besides advising the strict use of mosquito-nets for a personal prophylaxis, he urged especially a campaign against mosquitoes as the best measure for towns and cantonments, particularly against the dappled-winged mosquitoes, which breed principally in water on the ground.
But the Indian Medical Service was again not on his side. Ross was ordered to abandon the malaria work and report to a new post in Assam to do research on kala azar. “Columbus having sighted America was ordered off to discover the North Pole,” he remarked bitterly. “No, the man who can do is not allowed to do, because the man who cannot do is put in authority over him.”
Ronald Ross did not stop at identifying the vector for malaria and its habits. He was thrilled at the possibility of controlling this scourge for millions by controlling the breeding of the mosquito vector. Ross had proved that malaria was related more to the stagnant water in the pots, tubs, and tanks scattered around human dwellings where its vector bred in millions than to the marshes and pools as was believed until then. Ross’s discovery also explained the seasonal variations, the increase in cases during the rainy season, and how subsoil drainage that was practiced for centuries helped in controlling it. It was therefore enough to clear the breeding sites rather than drain a whole area, thus bringing down the expenses considerably. Ross did not stop at writing about malaria control either. He accepted the challenge to implement his ideas.
This remarkable finding, Ross later wrote, “brought him up standing.” As a final verification, he sent Mohammed Bux to capture a group of healthy sparrows. Mosquitoes that had fed on infected birds were allowed to bite these healthy ones. Within a few days the blood of the new birds was loaded with malarial parasites. At the same time he kept as controls a number of healthy birds in mosquito-nets, safe from the bites of mosquitoes, and found that none of them became infected.
He stood at the vanguard of implementing his ideas till his end. Ross attempted to eradicate malaria from England by forming ‘mosquito brigades’ to eliminate mosquito larvae from stagnant pools and marshes. In August-September 1899, he was sent to Freetown, the capital of Sierra Leone where he organised a sanitation drive, clearing the streets of tyres, bottles and empty cans and levelling roads so that rain water would not gather into puddles. But the Freetown malaria control programme did not yield desired results, probably because Ross had underestimated the number of breeding pools as well as the sheer number of vectors that he was trying to control. Ross had very limited funding and the best available technology was to pour oil on the numerous breeding sites around Freetown. As soon as the oil treatment stopped, breeding would begin again. Ross redoubled his efforts with increased funding from private sources and ensured the removal of all potential breeding sites, including rubbish, broken bottles and other potential water containers. Despite these concerted efforts, the programme was remembered more for its impact on the Freetown’s rubbish than for malaria control. J.W.W. Stephens and S.R. Christophers, who had worked with Ronald Ross in Freetown, organised a similar drive in Mian Mir in Lahore, India in 1901, without much success either.
Unperturbed by all this, Ross continued his single-minded work. To test Manson’s hypothesis that the parasites were ingested with water in which the mosquitoes had died while laying eggs, Ross fed the infected mosquitoes to healthy sparrows but the birds remained free of malaria. Now convinced that malaria did not spread that way, he continued to study infected mosquitoes. On the 2nd July 1898, he found in the thorax of a mosquito a large cell which contained within it several of the thread-like bodies. On July 4, 1898, examining the insect’s head, he found the the part of the mosquito to which these bodies were destined – the gland lay in the neck and upper thorax and it was the salivary gland. By July 8th, he was very sure: Malaria was passed back to the birds in the mosquito’s saliva during the act of biting. The exact route of infection was thus revealed.
The sanitation drive suggested by Ronald Ross was successfully tried elsewhere. During the U.S. military occupation of Cuba, a campaign against yellow fever and malaria was commenced at Havana early in 1901. Under the leadership of the Assistant Surgeon General William Crawford Gorgas of the United States Army the anti mosquito measures produced very marked results. Pyrethrum, a natural insecticide derived from the chrysanthemum flower, was first used by William Gorgas in Cuba where it was burned inside sealed dwellings. Mosquitoes entirely disappeared from many parts of the city, and were decreased everywhere.