Dengue fever also known as break-bone fever is a mosquito-borne viral disease occurring in tropical and subtropical regions, especially during the rainy season. The virus is called dengue virus (DENV) and has four serotypes, meaning that one can be infected four times and each time is severe than the last and can cause permanent damage to the body.
Presently dengue is common in more than 100 countries and almost forty percent of the world’s population, i.e. 3 billion people live in areas with a high risk of dengue fever. According to the Centre for Disease Control and Prevention, each year 400 million people are infected by the dengue virus, approximately 100 million get sick from infection, and 22,000 die due to severe dengue. Currently, dengue cases are on the rise in the Caribbean.
Dengue, in recent years, has been the biggest concern in India due to its hot and humid climate that is suitable for the growth of the dengue-carrying virus. In 2018 alone more than one lakh people in the country were diagnosed with dengue fever and 172 died of severe dengue. National Vector Borne Disease Control Programmer (NVBDCP) claimed that 2017 was an even worse year with 1.88 lakh dengue cases
Dengue is a mosquito-borne viral disease primarily transmitted by infected Aedes mosquitos, particularly A. aegypti of the Flaviviridae family and there are four distinct, but closely related, serotypes of the virus that cause dengue: DENV-1, DENV-2, DENV-3, and DENV-4. These are the same that spread the Zika virus and chikungunya virus. But these mosquitos aren’t born with viruses, rather when the bite a person infected with the virus they become infected and can spread the virus to other people. The humans are the primary host of the virus and when a female mosquito bites an infected person, the virus is transmitted to their body and in about 8-10 days the virus spreads to other tissues, including the mosquitos’ salivary glands which then transfers it to other people through their bites. The mosquito itself isn’t affected by the virus which they carry lifelong.
These mosquitos typically lay eggs in still and clean water stored in containers like buckets, bowls, animal dishes, flower pots, and vases. The mosquito lives both indoors and outdoors and tends to bite in the morning or evening but not necessarily at that time only. The infection can be acquired just by a single bite.
One of the causes of the spread of this virus is through its transmission from the mother to her fetus either during the gestation period or after birth during breastfeeding. Though, till now there is only one case registered where the virus was transmitted by the mother to her child
About four in one infected by the virus may get sick, which means that there is a chance that the infected may not even realize it but there are mild or severe flu-like symptoms also in infected. The incubation period, i.e. the time between the exposure and onset of symptoms is 3 – 14 days, but usually, it’s 4-7 days. The most common symptoms in both cases are nausea, vomiting, fever, rash, aches, and pain and, people with a mild case have symptoms lasting only 2-7 days.
Cases of severe dengue, although less in number can develop several problems like organ failure, severe bleeding or plasma leakage, and chances of death drastically increase when the disease is not managed properly. Cases of severe dengue caused an epidemic in the Philippines and Thailand in the 1950s and right now has heavily affected Asia and Latin America.
There are several methods for the diagnosis of dengue virus, which include virological tests and serological tests. A probable diagnosis, at home, can be based on finding fever with two of the following: nausea and vomiting, rash, generalized pains, or low white blood cell count. A tourniquet test can also be performed in areas with no laboratory available for blood testing, the test involves the application of a blood pressure cuff for five minutes, followed by the counting of any red or purple spots caused by a minor bleed from a broken capillary blood vessel; a higher number makes a diagnosis of dengue more likely.
There is no specific treatment for dengue, but methods can be used to control the symptoms. Fever reducers and pain killers can be taken to reduce the symptoms of muscle aches, pain, and fever. And for severe cases, consultation with physicians and nurses experienced in these situations is the best way to go about. Maintenance of the patient’s body fluid volume is critical to severe dengue care.
The first and foremost step is to stop the breeding of mosquitos, especially during the rainy season when water gets easily collected that can become a breeding area for mosquitos, disposing of solid wastes and cleaning of man-made areas that can collect water, covering, emptying and cleaning of water storage containers are some of the steps that can be taken up by the government and people too.
Along with this people should use personal household protection by using mosquito repellents, insecticides or window screens and, wear clothes than minimize body exposure to mosquitos. If already infected, they should avoid exposure to any further mosquito bites that can transfer the virus to the uninfected mosquitos who may in turn infect other people.
Knowledge is very important in these matters. Areas with high risk of dengue fever should be made aware of the virus and the symptoms and treatments available to fight the disease can help save many lives.