Tuesday, November 11, 2014

Chikungunya and Dengue Fever - A Public Health Responsibility

Zapped Aedes aegypti mosquitoes.
The small divisions on the scale are millimeters.
Nobody can tell me that I didn't have chikungunya, (chickV), although I'm not prepared to pay Ja$14,000.00 to confirm that diagnosis. Tests done on the a few hundred cases when the virus first appeared in Eastern Jamaica confirmed that is was indeed chikungunya. It spread quickly. It has got to the point now when we ask who hasn't had it, rather than who has had it. Nearly everybody on our street has had it.
     When it first arrived, it was made light of. "You'll have pains for about three days, maybe a rash, then you'll get better and will be immune to further attacks." Not so for many, including myself. Those of us over 45 may take 1 to 2 or more months to get over the acute phase. After that there is the possibility of the subacute phase with arthritis and the possibility of disorders of the blood vessels. Then there is the chronic phase, occurring beyond 3 months and persisting for 2 -3 years. The symptoms include prolonged and severe arthritis, fatigue, body weakness, and depression (no wonder, with the prospect of these symptoms for 3 years!) The chronic phase occurs in 13% of people who contract the disease. If 2 million people in Jamaica contract it, that means that about 260,000 will be affected for up to 3 years. More tragically, many people have died. Yes, they had other conditions such as sickle cell, hypertension and diabetes, or were undergoing cancer treatment, but without chickV they would still be alive.
     I think it is gross negligence on the part of WHO, PAHO and the Jamaican Ministry of Health, who were aware of this disease 2 years ago, to have done nothing. The least they could have done was to mount a public education campaign in the media, schools, churches and business places. The usual cry is that there is no money, but this outbreak has cost far more than a public education campaign would have. A public education campaign, at minimum could give the following information, which could be presented in simpler or more sophisticated ways depending on the audience.
1. Chikungunya is caused by a virus. What is a virus?
A virus is so small it cannot be seen with a regular (light) microscope, but only with an electron microscope. Viruses range in  size from 2 millionths to 30 millionths of a millimetre. What they lack in size, they make up for in numbers. We can have 100 trillion viruses in our bodies at the peak of infection.
2. How do viruses make us ill? 
Viruses consist of a protein coat surrounding a DNA (or RNA) core. The protein coat attaches to the outside of a cell in our bodies and the core is injected. It takes over the machinery of the cell and makes new viruses (about 10,000). Our cells burst open and lets them out to infect other cells. Each cell that is attacked dies. Different viruses attack different parts of the body.
3. What do our bodies do?
Our immune system manufactures antibodies to disable the virus. It takes about 5 days for the immune system to produce enough antibodies to get rid of all the viruses. After the viruses have been killed, some of the protein coats are still sticking to the outside of cells, so our immune system attacks these too, prolonging the symptoms.
4. How is the chikungunya virus spread?
It is spread by the female Aedes aegypti mosquito. (Males do not bite.) Aedes is a small mosquito which can be recognized by its stripey legs and body. It is around all day, and lurks under tables, beds and other pieces of furniture. It moves quickly, usually flying off before you can swat it.  There are over 50 species of mosquito in Jamaica, but Aedes is the only one that can transmit the chikungunya, and also dengue fever. When an Aedes bites a person infected with chickV, she sucks up some of the viruses in the person's blood. She will then digest the blood meal and find some water in which to lay her eggs. After about a week, she is ready for another blood meal. By that time, the viruses have moved from her stomach to her salivary glands. When she bites the next person, she injects some saliva to stop the blood from clotting while she sucks it up. The viruses are then let loose in that person's blood. It can take 2 - 7 days of incubation, during which time the viruses are multiplying, before the victim shows any symptoms. The mosquito can live for at least 3 weeks and bite many more persons. It could take only one infected person travelling from the site of the initial outbreak to another part of the country to take it there, without even being aware that they have the disease. Also, an infected person could be bitten by many mosquitoes. Alarmingly, an infected Aedes passes on the chikungunya virus to her eggs, which will give rise to mosquitoes already infected with the virus, without catching it from a person. Presumably, all subsequent generations will also carry the virus. Thus, the virus could remain dormant through the dry season, and re-emerge in the rainy season.
5. How can we stop it?
(i) Get rid of the mosquitoes, or stop them biting us -easier said than done. Adult mosquitoes can be killed by fogging, with malathion mixed with diesel oil,  which also kills other insects, including bees, and gives some people asthma. However, it is of limited usefulness, because the day after fogging, more mosquitoes hatch out. Using mosquito coils and vape - mosquitoes are becoming immune to these and they are not good for our health. Swatting them with a zapper - but you can't catch all of them.
(ii) Spray the skin with insect repellant containing Deet. I know people who have escaped ChickV this way, but surely it can't be good for you to spray yourself every day for months on end. It is good advice for tourists who are here for a few weeks.
(iii) Prevent Aedes from breeding. This should ultimately be the main form of control. In the limited public education we have had, people have been urged to check the following for mosquito larvae: flower vases, plant-pot holders, animal water containers, drums holding water for domestic use, old tyres, plastic bottles, styrofoam boxes and anything else that can catch water.
Careless garbage disposal leads to mosquito breeding.
Even if every householder followed these instructions, there are still too many places left where mosquitoes can lay their eggs - too many empty, overgrown lots in our towns and cities. There is one across the street from our house, and another one two houses away. Into these lots, people throw garbage which collects water in the rainy season. People living in the surrounding community are the target of mosquitoes which breed there, so it is really up to us to put pressure on the owners, or on Parish Council to get them cleaned up. Also, we need to be more responsible about garbage disposal. Business places shouldn't employ coke-heads to take away their garbage, knowing they will dump it on an empty lot or in a gully. We have an anti-litter law in Jamaica. Why is it not being enforced? Potholes in roads also fill with water in the rainy season, providing another suitable place for Aedes to lay their eggs.
"Too late now," we may say, as we've already caught ChickV, but there is the ever present threat of the 4 strains of dengue fever, including the life-threatening hemorrhagic dengue fever.
          A better long-term solution is to reduce the Aedes population significantly by releasing sterile males, which mate with females which then lay eggs which are not viable. Research into this by Oxitec has been going on for 10 years, and had now reached the testing stage. The method was successful in the Cayman Islands, just in time to spare them from chikungunya. They are now going on to test larger urban communities in Brazil. Their video is well worth watching.
     My final word is to those who work for WHO, PAHO, Ministries of Health in Caribbean countries, and governments who make the final decisions. We pay you. Without our taxes, you would not have the jobs you have. Jamaicans, already suffering under the IMF, now have to endure more pain as a result of chickV, when that pain could have been prevented. Is that fair?


petchary said...

This is great, Helen! Very comprehensive and I will share widely. Like you, I am a sufferer and five weeks later am still having arthritis pains and fatigue. You are right, we were not properly warned of all the implications of this horrible disease.

raising4princesses said...

well said, Ms. Helen. Today marks 5 weeks from my first pain and I still suffer most days. This past week I had a relapse and could not move for 4 days. My children have all complained of minor symptoms but nothing as severe as mine. Hope to see you soon and enjoy our chat on the beach. Maria

Helen said...

A young person like you should not be suffering as you are, Maria. Sorry to hear. Today is day 39 for me. My wrists were hurting so badly last night I had to get up and take a panadol.