The Health | jan/feb, 2020
18
column
Aids, polio and sepsis
How HIV can increase the risk of infections and cause sepsis
T
wo important events in the field
of infectious diseases in Malaysia
occurred one after another in
December 2019. The first was the
World AIDS (Acquired Immune
Deficiency Syndrome) Day 2019,
commemorated internationally every Dec 1
to raise awareness about the AIDS pandemic,
and a remembrance for those who have died
of the disease.
The other event was a more somber one,
with the unfortunate return of polio to
Malaysia. Both diseases are caused by differ-
ent viruses. There is still no vaccine or cure
for AIDS, while the polio vaccine has been
available commercially since 1961.
The difference in awareness
Due to increased awareness of AIDS, many of
us now know that the HIV virus (the causative
agent of AIDS) can be transmitted from an
infected individual to another via certain
body fluids such as blood, semen (cum),
pre-seminal fluid (pre-cum), rectal fluids,
vaginal fluids, and breast milk. It has not been
reported to be transmitted via saliva, sweat
and tears.
On the other hand, as polio vaccination
has been very successful in Malaysia (we have
been polio-free for 27 years until recently),
very few people, including the senior genera-
tion, remember how debilitating this disease
can be.
sepsis
Alert
Central
– Encephalitis
– Meningitis
By Assoc Prof
Dr Tan Toh Leong
&
Eyes
– Retinitis
Lungs
– Pneumocystis
pneumonia
– Tuberculosis
(multiple organs)
– Tumors
Assoc Prof Dr
Neoh Hui-min
Skin
– Tumors
How polio spreads
The polio virus is transmitted via the fecal-oral
route, usually via ingestion of water and food
contaminated with fecal material containing
the virus. It will then replicate and divide in
gastrointestinal cells, reaching the lymph
nodes and ultimately, the blood.
For polio, even though there will be
presence of virus in the blood (a condition
termed as “viraemia”), most patients
experience only minor influenza-like
HIV VIRUS DESTROYS
symptoms and usually will not develop
OUR IMMUNE CELLS BY
sepsis. In about one per cent of infections,
HIJACKING THEIR DNA
the polio virus will spread along nerve REPLICATION MACHINERY
fibers and destroy nerve cells in the central
AND USING THEM TO
nervous system, leading to paralysis.
PRODUCE COPIES OF
Fact
Infect to destroy
On the other hand, the HIV virus destroys our
immune cells by hijacking their DNA replica-
tion machinery and using them to produce
copies of itself.
The hijacked immune cells lose their func-
tion, and if a HIV positive individual is not
treated early, progressive loss of immunity
will lead to full-blown AIDS. As a result, AIDS
patients may die from infection or cancer due
to the shutdown of their immune systems.
Unlike polio, HIV positive individuals have
a very high risk of sepsis. During the early
stage of disease, these individuals experience
viraemia, i.e., presence of the HIV virus in
the blood.
Nevertheless, as stated in the previous
paragraph, the virus only destroys the
immune cells so that they can replicate.
It is the progressive destruction of the
immune system during the course of the
disease that renders HIV positive individuals
to be exposed and vulnerable to infections by
various microorganisms, leading to sepsis and
possible death.
Therefore, not surprisingly, severe sepsis
is a common cause of hospital admission for
HIV positive individuals and AIDS patients.
In addition, during the XVI International
AIDS Conference in 2006, researchers
reported the finding that “The final common
Main symptoms
of AIDS
ITSELF
Gastrointestinal
– Esophagitis
– Chronic diarrhea
– Tumors
pathway of untreated AIDS is progressive
immune-suppression over many years,
followed by an acute critical illness, usually
sepsis, and death, often within 48 hours.”
Therefore, sepsis is the most common and
quickest cause of death from AIDS.
HIV positive patients are now treated with
“HIV positive patients are
now treated with highly
active antiretroviral
therapy (HAART). The
first clinical trial involving
antiretroviral therapy for
HIV patients was initiated
in April 1995 by Merck
and the National Institute
of Allergy and Infectious
Diseases, USA.”
highly active antiretroviral therapy (HAART).
The first clinical trial involving antiretroviral
therapy for HIV patients was initiated in April
1995 by Merck and the National Institute of
Allergy and Infectious Diseases, USA.
There are now several classes of antiretrovi-
ral agents, and patients have been reported to
maintain low amount of viruses and delayed
AIDS development. Nevertheless, the best
prevention for AIDS still lies in behavioural
strategies such as practicing safe sex and
single-use needles for injectable drugs. —The
Health
How the poliovirus that causes polio looks like.
Associate Professor Dr Tan Toh Leong is a
Consultant Emergency Physician, Faculty of
Medicine, UKM and the Founder and President
of the Malaysian Sepsis Alliance (MySepsis)
Associate Professor Dr Neoh Hui-min is a Senior
Research Fellow, UKM Medical Molecular Biol-
ogy Institute (UMBI), UKM and the Secretary of
the Malaysian Sepsis Alliance (MySepsis)