Solar Eclipse from Rangpur, 22July 2009

google10f0934a5965041e.html

Solar eclipse is rare than lunar eclipse. Particularly full solar eclipse is very very rare. On 22nd July we enjoyed a such a full solar eclipse from many areas including Rangpur, Bangladesh. I have tried to have some picture with my nonprofessional experience but sky was somewhat cloudy particularly at the time of most exiting moment during full eclipse.

It could be injurious to eye to look at the sun particularly several minutes before and after the full eclipse. At this time our pupil become larger in size because light intensity become slows down. Our eye reacts like an automatic camera . It opens in darker and closes in brighter light. In extreme light size of pupil can be 0.1 mm in diameter and in darkest light it can as large as 9mm in diameter. So, during solar eclipse if its size become 3 or 4 mm in diameter the light from exposed part of the sun will enter in our eye on the macula with a effect of intensity of 30 to 40 times than other time of normal days and it is sufficient to burn our macula causing blindness. It can be compared with looking at torch light at night or viewing television in dark room which disturb our vision but not at day time. In any time intensity of the sun never goes down or increases or there is no variation of UV light coming to the earth from the sun. Looking at sun in normal days for few minutes or like may also causes burning our macula of eye.

Viral hepatitis and its vaccination

Hepatitis virus A (oral transmission)

Hepatitis virus B (parenteral transmission-injection)

Hepatitis virus C (parenteral transmission- e,g.injection)

Hepatitis virus E (oral transmission)

Viral hepatitis are common cause of jaundice in Bangladesh and other developing countries. There are several types of viruses responsible for hepatitis, they are type A, B, C, D, E, G etc. ( HAV, HBV, HCV, HDV, HEV, HGV). Among these HAV and HEV are commonly transmitted through oral route with contaminated food, drinks or water because these two virus are excreted in the stool of infected persons. Virus is carried by flies from stool or by cockroach from toilet and these may contaminate foods /drinks easily. Virus may contaminate water due to leakage of sewerage line or due to improper purification of water collected from river. Ice cream or any drinks/food kept in refrigerator made from contaminated water without prior boiling can also transmit viral as well as bacterial diseases. HAV is excreted 2 weeks before and 2 weeks after the onset of jaundice. So it can not be prevented easily. HBV,HCV and HDV are transmitted through parenteral route i.e, through blood transfusion or needle sharing and by sexual contact.

For the prevention of these diseases avoidance of open air defecation, use safe water for drinking or washing hands or utensil before eating ( not only filtered- but boiling or chlorination must) will prevent HAV or HEV infection. Vaccination for HAV is also available. For HBV vaccination is available and now it has been included in primary vaccination programme in Bangladesh recently.

Vaccination will prevent the respective viral disease against which vaccination has been given not the other viruses. From the above information it is clear that only two antiviral (hepatitis) vaccine are available in Bangladesh and also in other countries . So we must not feel safe after vaccination with these one or two types of antiviral vaccines, thinking, that viral hepatitis will occur no more. It should be noted that HCV is more dangerous than HBV and HEV is notorious than HAV.

So, we should be aware about the possible routes of transmission of viruses responsible for viral hepatitis or also other viruses and bacteria. We should not rely on vaccine only.