This
disease may be new to you and may be you may just brush aside saying,
"Well, this is none of my business!!" If you are thinking in that
line, wait a minute!! Let me share you common suffering from this disease,
which is rampant in low income settings. You may be avid hiker or trekker or
you may also have a plan to travel to countries like Nepal, India, and Pakistan.
When you get infected, whatever a person of strength and stamina, you will be
bed ridden so quick that you have to get hospitalized for weeks. During this
illness, you feel so miserable that you completely lose your appetite,
lethargic, aversion to anything food or even its smell, and you turn yellow
including your white of your eye bulb. Oh yes again, this disease is miserable,
and it is said, this disease takes hold in your body after you ingest food or
drinks that are contaminated with human soils. This happens in places, where
when there is poor water supply, sanitation and hygiene practices. Remember,
this may take the form of outbreaks affecting hundreds and thousands of people.
The worst part is if this disease affects pregnant women. There is high chance
of losing your pregnancy and even death of mothers due to liver complications
that lead to fulminant hepatic failure and painful death. We know, this disease
has not caught much of global attention like recent Ebola Virus Diseases, but
remember, this disease is like a silent death that spread invisibly like bush
fire with huge toll of illnesses and deaths in developing countries among impoverished
population.
HEV is a public health problem in low
income settings causing havoc in many parts of the country. For example, let me
share with you two outbreaks that provide clear perspective into the gravity of
HEV problem in our country. One was the confirmed HEV outbreak in the premises
of prime ministerial official residence
in the year 2007, where then prime minister himself, cabinet ministers
and other staffs caught this viral illness and bedridden for weeks. The second HEV outbreak is very
recent in the month of May and April, 2014, which occurred in the heart of Biratnagar municipality in eastern
part of the country. This outbreak was national headline, where thousands of municipality
residence was taken ill and some of them died. In both outbreaks, the root
cause for the disease outbreak was found to be the fecal contamination of
drinking water. These two recent examples could provide us with a sense of
urgency as to the extent of public health problem in Nepal that need to be
addressed with available preventive tools.
There
are few facts I need to write for our memory and keeping facts straight before
i conclude this series for next one. Here follows some facts on HEV:
- Incubation period (IP) is approximately 40
days
- most important acute viral hepatitis among
adults in much of central and southeastern Asia and the Indian
Subcontinent and the second most important hepatitis in the Middle east and
North Africa
- Up to 20 % clinical attack rate and an
associated high incidence of fetal wastage
- In endemic countries, genotypes 1 and 2
predominate and contaminated water is the major source of infection.
- Seronegative children and adults are at
general risk of disease and pregnant women are at special risk for severe or
fulminant hepatitis in endemic regions
- With regards to vaccination - HEV
vaccination is best suited to be included in EPI schedule rather than providing
this vaccine in campaign mode.
Before going into
preventive measures available for this illness, let us try to delve into
following discussion. To be more objective, I did a quick review of paper
in PubMed and was
fortunate to find series studies re: to HEV in Nepal since early 1980s. For our
convenience, let us try to dissect these studies as below:
1 Literature pre - 2000:
Almost all studies were conducted and reported from Kathmandu valley from early
as 1980s. Majority of the studies are hospital based done among admitted
inpatients supplemented with serological test for its diagnosis. Few studies
are also conducted among travelers or expatriate in the valley, Nepalese army
in UN mission - Haiti and notably among pregnant women. One study was not human
but done among local swine in the Kathmandu valley. The findings from these
studies suggested that HEV is endemic in Kathmandu valley of significant public
health importance and directly relates to poor water, sanitation and hygiene
practices. Also, one study reports that local swine population is the host for
this disease and suggests HEV as zoonotic illness. Another implication that
these studies brings to our notice are that travelers / expatriates visiting
Nepal are at risk; thereby this could affect tourism business. Also, there is
every likely that the disease could spread to other geographical locations.
2 Literature post - 2000:
All studies post-2000 add to HEV knowledge that have been gathered from studies
in Kathmandu valley. What stands out in these studies is most of them are
molecular in nature. These studies have clearly outlined the genotypic profile
of HEV circulating in Kathmandu valley. Also, other studies done among pregnant women diagnosed with HEV
infection adds to our knowledge that HEV remains serious threat to the health
of mother and unborn child. Additionally, one study add that HEV has been detected to rodents in Kathmandu so adding to
knowledge that some of the genotypes are zoonotic
in origin, which later has implication in designing measures to control and
prevention of this illness. Most important is that there was a conduct of HEV
vaccine trial among Nepalese army. The vaccine tested in this controlled trial
was “Hecolin” - which is licensed for use in China.
With
this background, I think, you can get a visual picture how common Nepali people
must be living their life in rural impoverished community. Well, some month
ago, when I wrote a brief note on cholera outbreak in some remote part of
Terai, I got a public comment that it is not what I depicted in my writing. But
we can hide the fact that there was an outbreak of significant impact in the
communities. This we cannot deny and I hope one of my friends could be in a
position to acknowledge that there exist challenges in clean water and
sanitation delivery to the much needed people. However, we can debate on this
public health issue. It can be controversial for those leaving in
affluence. One contention I would like to bring out and be vocal outright
with this background of long history of HEV studies with yearly outbreaks in
Nepal, how long do we have to wait for this HEV vaccine?
The
fruits of science have to be available for the community if the vaccine against
HEV is tested in the same population during its clinical development. Before
we go into technical jargon or say business case that is required for HEV
vaccine to secure its place in WHO prequalified list so we can use this vaccine
in public through UN agencies - let me walk you through some of the noise heard
for this vaccine in Nepal. Of other countries, I cannot objectively tell or
write now. But I can guess, same must be the case and scenario on other South
Asian countries, where HEV outbreaks occurs yearly in impoverished
population.
I Google - ed
"HEV in News in Nepal" - I came across pretty long list of online
news or even oped pieces. One stand out among those read and is written by Dr.
Buddha Basnyat in Nepali Times. This opinion piece (#Issue 591 - Feb 2012) strongly
states on possible public health use of HEV vaccine (in Nepal) comparing
with SA 14 - 14 - 2, live attenuated
vaccine against Japanese encephalitis (JE) also produced and
licensed in China. This vaccine was also not WHO pq ed at the time when Nepalese
health authority decided to use it country wide in endemic districts. This JE
vaccination started in campaign mode and later introduced into routine
immunization. This way, JE vaccination has been a successful program in
controlling and preventing debilitating serious brain viral infection. Now, we
see such a visible public health impact that anybody when travels to Terai
districts can hear such stories of success. The strength that lies hidden in
this endeavor is the background surveillance of Acute Encephalitis Syndrome
(AES), which provided clear picture as to the epidemiology of this disease, so policy
makers were able to provide direction for the country. If so is the case for
HEV vaccination in Nepal, my only question is “Do we have such robust
background surveillance data to guide our policy makers so they can take policy
decision?" Otherwise, i can agree to what Mr. Basnyat point of view, when
another HEV vaccine which was tested in Nepalese population - why not
make Hecolin (Chinese
vaccine) available for public health use here in Nepal?
One key constraint
is lack of comprehensive surveillance data to back up our argument for
introducing HEV vaccine in the community especially vulnerable population. So,
for me, I would love to see comprehensive epidemiological picture of HEV across
the country. Therefore, one way would be to review all the literature so far
published and use modeling tools, or conduct
surveillance (active vs. passive) based on availability of budget aligning with
interested parties to gauze and weigh the gravity of HEV problem in Nepal. Let
us see how far this will go or else may be, there must be a way to extrapolate
the findings of other country experience and create public demand for this
vaccine. In that case, the recent outbreak of HEV in Biratnagar could be one scenario;
we can build one for effective advocacy.
Where are we in its vaccine
development?
When we remember
those days of extreme weakness with bouts of vomiting with incessant nausea
that gripped your guts, we can now feel the suffering. However, it is
comforting to know so much have been studied on HEV and we do know the basic
epidemiology including the genotypic mapping of HEV circulating in Nepal.
Notably, some of the human phases of clinical trials were also conducted in
Kathmandu among Nepalese population.
However, there is
only one voice that we have heard and now I have started to understand why the
candidate vaccine meant for HEV is still not there in public health or even in
private market arena? In this aspect, I read a short letter in response to a paper published in a leading science
journal. Dr. Buddha Basnyat (a senior scientist seriously studying
infectious diseases in Nepal) has raised a serious ethical question as
to why vaccine industry or research organizations who have invested
so much of their time and money to develop HEV vaccine and now, there is no
vaccine when there is high demand in the community. In the letter titled
Neglected HEV and Typhoid Vaccine, he raises a serious question, “These
vaccines against hepatitis E.......are not available, despite their proven
efficacy and safety. If GSK, Walter....were not going to develop these vaccines
or make them available after their successful testing in Nepal and Vietnam, why
were they tested? And if these organizations will not develop them further, is
there a responsibility to make them available to others who might?"
HEV
is an area that needs much advocacy from the community and national level like
Nepal / India / Ethiopia, where HEV is still serious public health issue. We
should not wait for it instead we need to advocate to the global health
community. This is what i have been saying we should work simultaneously from
both end - at international fora as well build base at the community level and
have find a meeting point where international authorities and community health
leaders can sit together and have a meaningful but fruitful outcome from all
the penny invested in such study re: HEV or any other vaccines.
I
think, I have shared enough about HEV outbreaks in Nepal. Now, at my personal
level, a concrete research concept is what the need of the hour along with
active collaboration with academician and public health professionals in Nepal.
For this, we need to review papers so far published re: HEV in Nepal and find
out knowledge gaps where we need to address. Also, the key to what we plan can
only be successful if we partner with international organizations, who can
advocate on this problem at an international forum.
Therefore,
this planned review (that we need to write) has to bring out the comprehensive
HEV epidemiology in Nepal. It should also incorporate opinion from all
stakeholders, who has a role to play in bringing this much needed vaccine to
the community. Finally, we need to acknowledge that there is a huge demand for
HEV vaccine in countries like Nepal, Ethiopia, India, Myanmar. This has been
spelled out by leading physicians and researchers in Nepal as well. The only
remaining challenge is whether the voice of demand for HEV vaccine has reached
those who invest or has resources to focus available fund in this area or not?
I think, it has reached and it all lie within us how efficiently advocate on
this HEV issue at national or international level. Importantly, I believe we
have to raise awareness in the national as well as community level.
