Common fevers of Chennai

Chennai (previously known as Madras), is the capital of this southern state of Tamil Nadu. The weather is so hot that the British have a dish named after this city called Chicken Madras. Despite being dry most of the year, many infectious disease are prevalent throughout the year, only that some are more common during the rainy season. Infections are an important reason for high temperatures in the city.

The 5 common endemic infections in Chennai are:

1. Malaria – Vivax malaria is seen more often compared to falciparum malaria and typically cause high fevers with intense shivering (rigors). A person suffering typically experiences a cold phase with shivering, a hot phase with high fever and a sweating phase with drenching sweating. This happens periodically once a day or once in 2-3 days.

2. Typhoid fever (Enteric fever) – this is food borne infection caused by salmonella gastroenteritis. This can present variously but what is usual is that there would be some degree of a gastrointestinal upset. The patient could present with fever,shivering, body pains, headache,rash etc.

3. Dengue Fever – is another mosquito borne viral infection spread by the day biting Aedes aegypti (tiger mosquito – with white stripes on it) which is believed to bite below the knee. Fever can be high with shivering and severe back pain. A rash is also possible in light skinned patients.

4. Leptospirosis or Rat fever is caused by a family of 400 bacteria and causes fever with severe body pains. Some subtypes can cause jaundice, bleeding tendencies along with the fever whereas some others can cause kidney failure. This bacteria enters the body when water contaminated by rat urine (containing the bacteria) comes in contact with the body of the patient.

5. Scrub Typhus -happens due to a organism called Rickettsia and is a mite borne infection. The bite usually occurs in people who travel to heavily wooded areas such as IIT Madras or Raj Bhavan. The fever can be very high and the patient can have a very severe headache. Usually a black ulcer is found in the flexures of the body (under the breasts and in the groins)

The number one fever in Chennai over the last 2 years has been Covid 19. Patients usually have a fever with upper respiratory symptoms such as a headache, sore throat, runny nose, sneezing and cough with some phlegm production. A small proportion of patients develop a severe immune mediated pneumonia during the second week of the infection.

Urine infections, Intestinal infections, Skin infections are other common causes for fever. These infections are usually easily treated.Early diagnosis will help ensuring an early cure and rapid return to normal living.

How safe is Air Travel in the times of Covid?

Travelling anywhere isnt entirely safe in these days of the Covid Pandemic. Travelling puts you in contact with too many people who are potential transmitters of all kinds of infections including COVID 19. It was in the news recently about how a coach of a Australian Open Tennis player, who had tested negative before boarding the flight, was found to be positive on landing in Australia. This to me highlighted the medical risks of travelling. In this article , apart from my perspective, I also include some information that I got from an article from the Journal of the American Medical Association (JAMA).

Things that are supposed to prevent transfer of Covid 19 while travelling! The air inside the cabin is circulated in such a way that discourages respiratory droplets from spreading. The air from the overhead inlet flows downwards towards the floor level outlets. There is little airflow forwards or backwards between rows. I would presume that because they discourage people from standing inside the airplane, standing disrupts these air currents and scatters respiratory droplets. Crowding or seating passengers without gaps in between would probably put passengers at risk. Fresh air from out side the airplane is mixed with the HEPA filtered recycled air and recirculated inside the plane. The air movement inside is much faster than inside normal building on land. Therefore, features that increase safety of air travel are: 1. seating with gaps inbetween travellers. 2. discouraging passengers from standing inside the airplane. 3. HEPA filtered air that is circulated. 4. encouraging universal protective behaviour such as the wearing of masks by all, use of hand sanitizers before and after touching anything, avoiding face to face conversations, avoidance of touching eyes, mouth and nose and avoidance of hand shaking, high fives and kissing. 5. keeping the seat upright, this would probably maintain laminar airflow and prevent the spread of droplets. 6. avoiding food and beverage consumption would allow the traveller to keep his mask (protection) ON at all times.

Whatever said, the estimated risks of transmission of COVID 19 infection is believed to be small . In one study from China among contacts of 2300 known cases aboard high speed trains, an overall transmission rate of 0.3% was noted.

from JAMA

Factors that increase the risk of COVID transmission during flight. 1. You being unaware or careless about your risk of transmitting infection to others. The Virus has an incubation period of upto 14 days , so you may not develop symptoms for 2 weeks after you travel. People become infectious and can transmit the infection 2 days before the onset of symptoms (such as fever, cough, cold, body pains, loss of smell and taste etc). It is difficult, virtually impossible to determine where and when you caught the infection. You could have caught the infection when shopping at the mall, travelling by public transport, meeting with a few friends, attending a social gathering of any kind. After 5-14 day incubation period you may develop symptoms (25% of those infected may be asymptomatic) You could start spreading the infection to others 2-3 days before you become symptomatic. Questioning asymptomatic people about where they travelled, whom they met or even if they have any symptoms before they boarded their flight is may be very difficult.

2. Five things that are advised to prevent the spread of COVID 19 are very difficult to practice while travelling (Avoiding crowds, keeping 6 ft distance from everyone around you, wearing a face mask all the time, not touching your eyes, nose and mouth and finally washing your hands or using a sanitizer every 20 mins) 3. Spending >15 mins sitting <6 feet from others and talking face to face without masks are believed to be high risks for spreading infection to others. These things cannot always be avoided while travelling. Just checking in your baggage or sitting inside a crowded airplane may put you at high risk!

What the Airports and Airlines are doing to prevent COVID spread? 1. Questionnaire for all to fill out – regarding the presence of symptoms of infection – with warning that those who have symptoms wont be allowed to travel! I am sure that many would rationalize that it was only an allergic cold , that their symptoms wasnt COVID or just not tell the truth because they have an urgent need to travel! 2. Check temperature for eveyone. 3. Enhanced cleaning and disinfection of airplanes and airports. 4. Contactless boarding and baggage processing. 5. Use of physical barriers to maintain physical distancing. 6. compulsory use of face masks. Provision of face shields, sanitising towelettes, hand sanitizers to all. 7. Seperation between passengers on board or the supply of PPE kits for those sitting in the middle seats. 8. Minimising food and beverage services to limit contact and to limit pulling down of masks. 9. Controlled access to aisles and toilets on board the aircraft. 10. Limiting cabin luggage, staying seated and following crew instructions and to sanitize hand frequently.

Take home message for the passenger. Not to travel in case you have a fever, coldor a new cough! While airports and airlines are taking all necessary precautions, it is important that each and every one of us do our bit to prevent the spead of this dreadful disease to not only our loved ones but also to people in other parts of the world.

The end………