Sunday, March 8, 2020

CORONAVIRUS

Coronaviruses (CoV) are a large family of viruses that cause illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS-CoV) and Severe Acure Respiratory Syndrome (SARS-CoV). A novel coronavirus (nCoV) is a new strain that has not been proviously identified in humans.

Coronaviruses are a family of viruses that cause disease in animals. Detailed investigations found that SARS-CoV was transmitted from civet cats to human and MERS-CoV from dromedary camels to humans. Several known coronaviruses are circulating in animals that have not yet infected humans.

The new coronavirus, officially called Covid-19 currently has fatality rate between 0.7 per cent to 3.4 per cent. This is much lower than fatality rates for Mers (30 per cent) and SARS (10 per cent), but still a significant threat. However, the new coronavirus (Covid-19) is spreading fast. The bulk cases and fatalities have been confined to China, but the virus is spreading internationally.

The source of the coronavirus is believed to be a "wet market" in Wuhan which sell both dead and live animals including fish and birds. Such markets pose a heightened risk of viruses, jumping from animals to humans because hygiene standards are difficult to maintain if live animals are being kept and butchered on site. Typically, they are also densely packed.

The animal source of the latest outbreak has not yet been identified, but the original host is thought to be bats. Bats were not sold at the Wuhan market but may have infected live chickens or other animals sold there.

Bats are host to a wide range of zoonotic viruses including Ebola, HIV and rabies.

Scientist in China believe that Covid-19 has mutated into two strains, one more aggressive than the other, which could make developing a vaccine more complicated.

It is impossible to say which way the disease will go but, on its current trajectory, it is likely to spread to more countries, affecting many more people. The number of cases is beginning to decrease in China but is increasing in the rest of the world.

Initial common symptoms of Covid-19 include fever, dry cough, tiredness and a general feeling of being unwell. In more severe cases, infection can cause pneumonia, severe acute respiratory syndrome, kidney failure and even death. Symptoms are thought to appear between 2 and 10 days later after contracting the virus, but it may be up to 24 days

The virus is spread via droplets when a person coughs or sneezes. The droplets land on surfaces and are picked up on the hands of others and spread further. People catch the virus when they tough their infected hands to their mouth, nose or eyes. Standard recommendations to prevent infection include regular hand washing, covering mouth and nose when coughing and sneezing, thoroughly cooking meat and eggs. Avoid close contact with anyone showing symptoms or respiratory illness such as coughing and sneezing.

Various crazy conspiracy theories have been circulating that the virus somehow escaped from a Chinese lab, either by accident or design. However, that is categorically untrue and scientists studying its genetic code have linked it to bats. It probably then jumped to another animal, which passed it on to humans.

The 1918 Spanish Influenza or the H1N1 virus remains the most devastating flu pandemic in the modern history. The disease swept around the globe and is estimated to have caused between 50 to 100 million deaths. A version of the same virus was also behind the 2009 swine flu outbreak, thought to have killed as many as 575,400 people.

Other major influenza outbreaks include Asian flu in 1957, which led to roughly 2 million deaths, and Hong Kong flu which killed 1 million people 11 years later.

But coronavirus outbreaks have so far been far smaller. Sars eventually spread to 27 countries in total, infecting around 8000 people and killing 700

Tuesday, September 3, 2019

Dengue Fever

Dengue fever is a painful, debilitating mosquito borne disease caused by any one of four closely related dengue viruses. These viruses are related to the viruses that cause West Nile infection and yellow fever.

An estimated 400 million dengue infections occur worldwide each year, with about 96 million resulting in illness. Most cases occur in tropical areas of the world, with the greatest risk occurring in the Indian sub continent, Southeast Asia, Southern China, Taiwan, the Pacific Islands, the Caribbean (except Cuba and the Cayman Islands), Mexico, Africa, Central and South America (except Chile, Paraguay, Argentina)

Dengue fever is transmitted by the bite of an Aedes mosquito infected with a dengue virus. Its peak biting periods are early morning and before dusk. The mosquito becomes infected when it bites a person with dengue virus in their blood. It cant spread directly from one person to another person.
Transmission of Dengue virus
Symptoms of Dengue fever usually begin four to six days after infection and last for up to 10 days, and may include sudden high fever, severe headaches, pain behind the eyes, severe joint and muscle pain, fatigue, nausea, vomiting, skin rash which appear two to five days after the onset of fever,mild bleeding such as nose bleeding, bleeding gums or easy bruising.

Sometimes symptoms are mild and can be mistaken for those of flu or another viral infection. Younger children and person who have never had the infection before tend to have have milder cases than older children and adults. However, serious problems can develop. These include dengue hemorrhagic fever, a rare complication characterized by high fever, damage of lymph and blood vessels, bleeding from the nose and gums, enlargement of the liver, and failure of the circulatory system. The symptoms may progress to massive bleeding, shock and death. This is called dengue shock syndrome (DSS).

People with weakened immune systems as well as those with a second or subsequent dengue infection are believed to be at greater risk for developing dengue hemorrhagic fever.

Doctors can diagnose dengue infection with a blood test to check for the virus or antibodies to it.

There is no specific medicine to treat dengue infection, If you think you may have dengue fever, you should use pain relievers with acetaminophen and avoid medicines with aspirin, which could worsen bleeding, You should also rest, drink plenty of fluids and see your doctor. If you start to feel worse in the first 24 hours after your fever goes down, you should get to a hospital immediately to be checked for complications.

The best way to prevent the disease is to prevent bites by infected mosquitoes, particularly if you are living in or travelling to a tropical area. This involves protecting yourself and making efforts to keepk the mosquito population down.

To protect yourself
Use mosquito repellents, even indoors
When outdoors, wear long sleeved shirts and long pants tucked into socks
When indoors, use air conditioning if available
Make sure window and door screens are secure and free of holes. If sleeping areas are not screened or air conditioned, use mosquito nets
If you have symptoms of dengue, speak to your doctor

To reduce the mosquito population, destroy the mosquito breeding grounds and spray insecticide in the affected areas. These include old tires, cans. or flower pots that collect rain. Regularly change the water in outdoor bird baths and pet's water dishes.

If someone in your home gets dengue fever, be especially vigilant about efforts to protect yourself and other family members from mosquitoes. Mosquitoes that bite the infected family member could spread the infection to others in your home.