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The National Institute of Virology in the city had recently declared that there was an epidemic of Chikungunya viral fever in Pune. Sujata's physician managed to acquire an imported diagnostic kit and confirmed that she was a victim of this disease. A doctor in his early forties, he had never seen a case of this fever before. It was more than a month before Sujata could resume her daily chores. Today, almost a year later, she still complains of pain in her ankles. She now wears only cushioned footwear, to ease the discomfort.
Chikungunya fever is a relatively rare debilitating viral disease that spreads through mosquito bites. Occasional outbreaks were common in the tropics. After a silence of almost 30 years, India suffered a massive epidemic of this crippling disease in 2006. The Indian Ocean islands of the Seychelles, Madagascar and the Comoros also witnessed the wrath of this illness. For the first time ever, there was an epidemic in French Reunion Island in 2005.
This disease made international news again last month, when a tourist was bitten in southern India, and got the fever upon returning home to Castiglione town in Ravenna province of Italy. Doctors were alarmed to discover that local mosquitoes got infected after biting him and started spreading the disease in the province. This was the first ever case of local transmission of chikungunya disease in Europe.
There are now 78 confirmed cases of this disease and more than 250 are suspected, according to health officials. This is the first time an outbreak of chikungunya has been confirmed outside the tropics.
The authorities are worried that if the outbreak is not contained, it might spread into neighboring European countries, creating an epidemic.
The Chikungunya virus first originated in Tanzania in 1954. It was introduced into Asia some time later. There have been outbreaks of the fever on and off through the years in the countries in sub-Saharan Africa and Asia-Pacific. But the magnitude of the disease seen in India in 2005-2006 was unprecedented. Almost 1.3 million people were affected by the disease. Several thousand more cases went undiagnosed and unreported. Reunion Island reported some 250,000 cases.
This disease spreads through the bite of our age-old foe, the mosquito. The two types of mosquitoes incriminated are Aedes aegypti and Aedes albopictus. While the former is rampant in Africa and Asia-Pacific, the latter has a broad distribution in Europe, the southern United States, the Caribbean and Latin America. Studies show that the Aedes mosquito has evolved in the past 50 years so that it is now able to adapt to almost all types of climates.
Contrary to the mosquito-borne fevers of malaria and dengue, chikungunya fever is not a killer. But it attacks multiple joints causing severe disability. There is excruciating pain accompanied with massive swelling. In some parts of India, it was referred to as "hatti" gunya (hatti meaning elephant).
Although the disease is self limiting, it takes several weeks to a few months for the joint pain and swelling to subside. In some cases, it even takes a year or more. Until then, the patient is practically immobilized and unable to follow a normal routine. In occasional cases in India, it precipitated rheumatoid arthritis, a painful, chronic disease of the joints.
The name chikungunya comes from the Makonde language of Tanzania and Mozambique and it means that which bends up or becomes contorted. This refers to a patient suffering from the incapacitating disease.
India had last witnessed the fever in 1973. After that, there were some sporadic episodes, but none deserving as much attention. Scientists are not quite clear of the reason of this sudden comeback of the virus with a vengeance. Several theories have been put forth to explain the trigger for the infection.
"This virus stimulates the immune system very strongly. It gives long lasting immunity to a patient. Perhaps, that is why the disease did not surface for the past 30 years. You see, it was the young population that was strongly affected now. They did not have any previous exposure to the virus," notes Dr. Dakshayani Pandit, a microbiologist in Pune.
Scientists believe that the reason for the re-emergence of this disease is manifold. Increased global population and widespread international trading leading to population migration and globalization have led to the spread of the disease across international borders. After all, a mosquito or a virus does not recognize manmade borders.
Within countries, increased urbanization has led to increased population density in the cities. In developing countries, this is accompanied by poor housing, poor sanitation and water accumulation that promotes breeding of the mosquitoes. Lack of awareness of the mosquito threat due to lack of education and deficient public health measures worsen the situation.
Forests are the natural habitat of this vector. With more and more deforestation, the habitat naturally shifted into urban areas. Moreover, felling the trees has made the weather hotter and these mosquitoes thrive in hot and dry weather.
It is also speculated that over the past several years, the virus has undergone various mutations. These facilitate rapid spread of the virus and enhance its pathogenecity, making it more virulent now. Perhaps that is the reason for the occasional aberrant complications seen in some parts of the world.
The genus alpha virus, to which this virus belongs, is known to affect the brain and liver. But the chikungunya virus is dreaded only for joint affections. Yet, during the epidemics in the past two years, there have been isolated cases of encephalitis (inflammation of the brain tissue) and hepatitis due to chikungunya on Reunion Island. Doctors in New Delhi even came across a case of nephritis (inflammation of the kidney) as a complication of chikungunya.
Hospitals on Reunion Island noticed for the first time a transmission of the virus from a mother to a fetus. This resulted in some fetal deaths and fetal malformations.
Although this fever is not fatal, some deaths have been noted, probably as a result of such complications arising from the disease. These new presentations have confused and alarmed the health providers worldwide.
The arthritis induced by the fever cripples not just the patient, but by affecting his productivity it cripples his family, his community and the country at large. In a developing country like India, a large percent of the population survives on daily wages. When the sole earning member in a family is bedridden for months on end, one can only imagine the vicious trap that the family falls into -- lack of income, more poverty, worsened living conditions, more malnutrition, more disease and more deaths.
Long-term absence of the productive workforce badly affects various industries and thus the national economy. In the world of today, the economy of one country is always linked with that of at least one another country. So such an epidemic in one country produces global economic repercussions.
Sadly, since this virus did not surface for many years, it was considered to have disappeared. It was not adequately researched before and not enough is understood about the natural history of the disease. A paucity of epidemiological information and absence of proper knowledge left physicians utterly unprepared to handle the epidemic when it hit India in 2006. There were not even enough diagnostic kits available and they had to be imported to confirm clinical suspicions.
There are no vaccines to prevent the disease and there are no anti-viral drugs to kill the virus. The only treatment is medicines to control the fever and pain. Shielding oneself from the vector is the only available weapon today.
The same old messages of "store water safely, prevent waterlogging, prevent mosquito breeding, protect from mosquito bites" once again need to be underscored. Research is under way to make a vaccine against the disease, but until then there is only one slogan for one and all -- prevent mosquito bites, contain the vector.
Developing nations need to divert their finances toward public health and sanitation today to escape catastrophic economic consequences tomorrow, resulting from the lack of these. Global health organizations also need to lend them a supporting hand. Long ago, such diseases were isolated problems of poor nations. But times have changed. The case of the Italian patient is a testimony that problems of poor nations are no longer theirs alone and justifies the need for establishing global measures for controlling vector-borne diseases.
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(Dr. Pradnya Kulkarni is a clinical pathologist. She worked as a consultant pathologist in a private laboratory in Pune before moving to Hong Kong with her husband and young daughter. She is also a freelance writer, focusing on medical issues of public concern. ©Copyright Pradnya Kulkarni.)
