Dengue fever “en mass” has had its day, at least
until the next wave, and the Typhoid fever epidemic seems
to be waning. Now it’s Japanese Encephalitis (J.E.)…..the
latest fear factor. Newspaper reports state 50 plus cases
so far. I seriously doubt that these figures are accurate.
Many cases in smaller dusuns or villages may never be reported,
or indeed ever seek medical attention. Other reported cases
may not be J.E. at all, but any one of the many kinds of Encephalitis
or Meningitis (infection of the brain). Some people will contract
the disease and never show symptoms. However with J.E. being
the most common form of Encephalitis in this part of the world
(30,000 – 50,000 anually throughout Asia), one would
tend to agree that J.E. really is here.
One other factor putting us slap bang in the middle of a
risk zone is the favorite Balinese dish, “Babi Guling”
or “Spit Roasted Pig”. Don’t panic if you
have recently indulged in this dish, or even if bacon is your
favorite breakfast food. Ingesting pork will not give you
J.E., but the mosquito that bites your breakfast while it’s
still walking will!
What Is Japanese Encephalitis ?
J.E. is a serious viral illness that affects the brain. It
primarily affects children between the ages of 2 – 10
years, the elderly, or individuals with lowered immune systems.
Case fatality rates range from 0.3 – 60% (average 30
%), and approximately 30% of those survivors will be brain
damaged in some way. It’s no wonder that this outbreak
has struck fear and panic into the community at large.
How does Japanese Encephalitis present ?
Some people that are exposed to the disease will have very
mild, or no symptoms at all. Those people will not go on to
develop serious consequences of the disease, indeed they will
probably never know that they had the disease. Those that
suffer severe acute infection would show any or all of the
following signs:
l Abrupt onset of high fever.
l Headache.
l Loss of appetite.
l Pain behind the eyes.
l Neck stiffness
l Disorientation or stupor.
l Convulsions or twitches / tremors.
l Coma.
l Paralysis.
PERSONS EXHIBITING ANY OF THE ABOVE SYMPTOMS MUST SEEK MEDICAL
ATTENTION IMMEDIATELY.
How do people get Japanese Encephalitis?
J.E. is spread by vector transmission, the Culex Mosquito
being the carrier. It cannot be transmitted directly from
one person to the next, (i.e. you cannot get it from touching
or kissing an infected person).
Mosquitos become infected by feeding on pigs or wild birds
infected with the J.E virus. Infected mosquitos then transmit
the virus to humans during the feeding process. The Culex
mosquito typically inhabits rice paddies, and other waterways.
This mosquito is essentially an outdoor mosquito, and they
are most active in the late evenings or at night.
Not all Culex Mozzies are carriers of the disease. Only mosquitoes
that have been infected can infect you.
How do we prevent the spread of J.E. ?
Firstly, don’t invite this troublesome insect into
your area by providing it with ideal breeding grounds.
v Make sure that your garden and surrounding area are free
of water catchments, or that water containers are covered.
v Keep larvae eating fish, such as guppies, in ponds.
v Use chemical larvicides in ponds, drains or other water
catchments.
v Remove garbage, or unnecessary pots, bottles, cans etc from
the garden area.
v Lush garden areas should be fogged regularly in the monsoon
season.
… and secondly, don’t get bitten !
v Mozzie coils, or vapour mats can be used indoors in the
early mornings and late afternoons during the wet season.
v Mosquito nets, and screens can be used in problem areas.
Babies should always be protected by cot, or pram covers.
v Wear long sleeved, loose light colored clothing while walking
in garden areas.
v Personal repellants may be used, however, they should be
used with caution in the very young, or the elderly.
While various health authorities class travelers in the very
low risk category for J.E., the same cannot be said for the
resident or expatriate. Anyone living adjacent to rice paddies
(therefore wild birds), or who have neighbours that keep pigs
in their back yard may consider themselves at risk………(Ooops.,I
think that includes me !!!) If you have heard of any cases
(confirmed or otherwise) which may have originated in your
general area, you should consider yourself at a high risk.
The Vaccine.
A vaccine is available against the J.E. virus, however there
are a few problems with this. Firstly, (last I heard) there
is no vaccine currently available on the Island. Those centers
that do stock the vaccine have waiting lists pending supplies.
The vaccine is very expensive. A course of three vaccines
can cost upwards of a million rupiah. If you have a large
family to protect, or fall into the lower socioeconomic group,
this can be quite an outlay.
There have been nasty side effects reported following injection
with the J.E. vaccine. About 0.6 % of patients have developed
severe rashes and swelling immediately after the vaccine and
up to 10 days after receiving the vaccine. It is wise therefore
to remain close to medical facilities for up to 10 days after
the last dose. The good news is that the vaccine has a high
efficacy. This means that once the course has been completed,
it gives a high (almost 100%) immunogenic response. It is
very effective.
The current J.E. vaccine schedule is a course of 1.0 ml of
the vaccine injected on days 0, 7 & 30. (half the dose
for children aged 1-2 years). A short course can be given
over 2 weeks (days 0,7 &14) when time does not permit
the longer course, however it is not as effective as the longer
course. Adequate antibody response is achieved 10 days after
the last injection. Protection following the primary course
of the vaccine is said to last approximately 2 years, therefore
most authorities recommend single booster shots at 2 year
intervals following the primary course.
So…If I do get Japanese Encephilitis, how is it treated
?
Firstly, there is no curative treatment for J.E. (i.e. no
magic pill, injection etc. that will cure it). J.E. is treated
symptomatically by reducing the fever, analgesics for headache,
sedatives for seizures and specialized intravenous therapy
to reduce cerebral swelling.
So once again it’s time to wage all out war on that
pesky insect!…..’til next edition stay happy,
stay healthy and stay young, and keep on swatting that mozzie!
Kim Patra is a qualified Registered Nurse / Midwife, and
mother of three, who has been living and working in Bali for
past 15 years. She has assisted many traveller (... and others)
either as a flying medical escort or just a voice on the end
of the phone! Kim is happy to discuss any health concerns
that your may have. Her e-mail contact is info@chcbali.com
