Dr. Edith Breburda
published in : FIAMC March 9, 2016
Scientists from Uganda were the first ones who isolated the Zika virus. In April 1947 rhesus monkey 766 was part of a Yellow Fever study. He lived in a cage near the little Zika Forest in Uganda.
In 1952,
researchers from the Uganda Virus Research Institute in Entebbe started with
more exhaustive studies, and inserted the virus in numerous monkeys, cotton
rats, mice, guinea pigs and rabbits. The
Zika virus caused damage to the neurons only in mice. No other evidence of a disease was
shown. One of the 24 papers, published
in the following 30 years concluded: “The absence of recognition in humans, of
a disease caused by Zika virus does not necessarily mean that the disease is
either rare or unimportant.”
In 1964 David
Simpson, a student of Zika co-discoverer George Dick, reported that he became
ill when working with Zika strains isolated from mosquitos at the Entebbe lab that discovered the virus. Simpson described his symptoms as “mild”. He
wrote: “If this was a typical infection with Zika virus it is not surprising
that under normal circumstance the virus is not isolated frequently from man.”
1973 C. Martins
described the symptoms of another Zika infection in the Journal Archive. “The lab technician worked with
the Portugal’s Institute of Hygiene and Tropical Medicine in Mozambique, when
he developed fever accompanied with some pain in his joints. He recovered completely after one week.”
In the 70’s and
80’s, Zika antibodies where found in wild monkeys in Nigeria and
Indonesia. Documented cases of infected
people remained scarce, until the New
England Journal of Medicine reported 49 confirmed, and 59 probable, Zika
cases in 2009.
The outbreak of
the disease occurred two years earlier at Yap Island. No one was hospitalized or died. surprisingly
no mosquitos with the virus were found.
Since then,
Zika infections began to increase. In the US, one traveler infected his wife,
presumably through sex. Before Zika
swept across the Caribbean and through Latin America, it had been recorded in
French Polynesia in 2013. In 19,000 suspected cases, 333 had been
confirmed. For the first time did the
symptoms include neurological disorders (1).
Zika
could cause congenital infections and microcephaly. so far, though, we have not
seen numerous headlines reporting that people who encounter the virus can
become temporarily paralyzed.
On Monday, March 7 2016, The Lancet medical journal provided
evidence that the virus can also cause people to become temporarily
immobile. This was the first report of a
possible link between the Zika virus and Guillain-Barré syndrome. This condition, that contributed to several
kinds of infections, was first described 1916 by French doctors Georges
Guillain and Jean-Alexandre Barré.
Guillain-Barré syndrome develops
when the body’s immune response to an infection attacks its own nervous system. “It is an autoimmune attack that happens when
part of a virus resembles part of human cell,”
explained Hugh Willison, who studies the disease at the University in Glasgow
in Scotland. He continued: “Like other viruses, the one that causes Zika
hijacks a cell’s own replication machinery to
make new copies of itself, which then break
out of the dying cell and infect neighboring cells.”
Doctors treat such
patients with a mix of antibodies made from healthy donors, or a plasma exchange is used, in which the body’s red cells
are separated from the immune-cell-carrying
plasma, and then returned to the body (2).
For researchers, the question
remains how Zika-virus is causing such damage to the unborn. Previously done scant research has resulted
in few insights. It remains difficult to prove a link between the virus and the
defects, because blood tests for Zika are only accurate for the first week
after the infection.
Researchers at John Hopkins
University in Baltimore, Maryland, and Florida State University in Tallahassee,
conducted experiments to determine the virus’ possible effects on the
developing brain. Because the access to
fetal human brain tissue is limited, induced pluripotent stem cells (iPS), (harvested
adult cells that have been reprogrammed) have been deployed as an in-vitro
model. For control purposes, Zika was
exposed to human embryonic stem cells, (obtained by the destruction of
embryos)/(3).
The
neuroscientists Dr. Hongjun Song and
Guo-li Ming, and the virologist Hengli Tang, reported in a Cell
Stem-Cell article, from March 2016, that 85% of the neuronal and immature
brain cells cultures had been infected after three days; only 10% of fatal
kidney cells, human embryonic stem cells, and undifferentiated iPS cells were
infiltrated by the virus.
The two
independent studies showed that the virus also “took the cells over.”
“The infected cells
had not been killed right away. Instead,
the virus “hijacked the cells,” using the cellular machinery to replicate
themselves. The infected cells grew more
slowly through cell population and interrupted cell division cycles, which
could also contribute to microcephaly.
We still need to figure out how the virus crosses the placenta and
infects the fetuses directly, something most viruses can’t do”, says Dr.
Song. He continued: “Plenty of questions
about Zika virus and its apparent link to birth defects remain unanswered.” The team will repeat its study with other
flavi-viruses (4).
The first Zika studies where
conducted with monkeys, cotton rats, mice, guinea pigs and rabbits. The
recently diseased First Lady Nancy Reagan was in favor of human embryonic stem
cell research. We might remember Nancy’s
words in 2004. It was before the President’s
death when she said: “Ronnie’s long journey has finally taken him to a distant
place where I can no longer reach him.
Because of this, I’m determined to do whatever I can to save other
families from his pain.”
Many Republicans have been
scandalized, when the beloved first Lady campaigned for broader human embryonic
stem cell research in order to discover a cure for Alzheimer’s. So far, the death of many unborn babies has
not resulted in any remedy.
While Human Rights Commissioner’s call for abortion, and want
to change the laws in developing countries with disabled unborn that show the
sign of microcephaly, bishops explain that you cannot treat Zika virus infections
by killing human beings. The Holy See states
that children with birth defects are to be protected and cared for throughout
their lives, in accordance with our obligation to safeguard all human life,
healthy and disabled, with equal commitment (5).
1) Cohen J.: Zika’s
long, strange trip into the limelight. Science, February 8, 2016
2) Vogel G and
McLaughlin K.: Why does Zika leave some
patient paralyzed? Science, March 3, 2016
3) Hengli Tang
et al:. Zika Virus infects human cortical
neural progenitors and attenuates their growth. Cell Stem Cell, in Press corrected proof, available online, March
4, 2016
4) Vogel G.: Zika
virus kills developing brain cells. Science, March 4, 2016.
5) Wright W.:
UN Human Rights Chief Scolded for denying
rights to disabled Babies. C-Fam, Center for Family and Human Rights, February
18, 2016
Please see also: E. Breburda: Reproduktive Freiheit, free for what? 2015, ISBN-10:
0692447261, ISBN-13: 978-0692447260 / kindle e-book.
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