Jump to content
IndiaDivine.org

Officials say vaccine caused Nigeria polio

Rate this topic


Guest guest

Recommended Posts

By MARIA CHENG, AP Medical Writer 46 minutes ago

 

A polio outbreak in Nigeria was caused by the vaccine designed to stop

it, international health officials say, leaving at least 69 children

paralyzed.

 

It is a frightening paradox in a part of the world that already

distrusts western vaccines, making it even tougher to stamp out

age-old diseases.

 

The outbreak was caused by the live polio virus that is used in

vaccines given orally — the preferred method in developing countries

because it is cheaper and doesn't require medical training to dispense.

 

" This vaccine is the most effective tool we have against the virus,

but it's like fighting fire with fire, " said Olen Kew, a virologist at

the U.S. Centers for Disease Control and Prevention.

 

The CDC and the World Health Organization announced the cause of the

polio outbreak last week, even though they knew about it last year.

 

Outbreaks caused by the oral vaccine's live virus have happened

before. But the continuing Nigerian outbreak is the biggest ever

caused by the vaccine. It also follows a nearly yearlong boycott of

the vaccine in Africa's most populous country because of unfounded

fears the vaccine was a Western plot to sterilize Muslims.

 

Officials now worry that the latest vaccine-caused Nigerian outbreak

could trigger another vaccine scare.

 

Experts say such outbreaks only happen when too few children are

vaccinated. In northern Nigeria, only about 39 percent of children are

fully protected against polio.

 

The oral polio vaccine contains a weakened version of polio virus.

Children who have been vaccinated excrete the virus, and in unsanitary

conditions it can end up in the water supply, spreading to

unvaccinated children.

 

In rare instances, as the virus passes through unimmunized children,

it can mutate into a form that is dangerous enough to spark new outbreaks.

 

In 2001, officials reported that 22 children were paralyzed from polio

in the Dominican Republic and Haiti in this way. Subsequent

vaccine-caused polio outbreaks have occurred in the Philippines,

Madagascar, China and Indonesia.

 

In the West, the polio vaccine is given as a shot and uses an

inactivated virus, but that method is more expensive and requires

training.

 

In Nigeria, the outbreak comes " in the wake of all the other problems

they've had in, " said Dr. Donald A. Henderson, who led WHO's smallpox

eradication campaign in the 1970s.

 

In 2003, politicians in northern Nigeria canceled vaccination

campaigns for nearly a year, claiming the vaccine was a Western plot

to sterilize Muslims. That led to an explosion of polio, and the virus

jumped to about two dozen countries.

 

Now, health officials' decision to keep quiet about the cause of the

outbreak for so long may look suspicious.

 

Dr. David Heymann, WHO's top polio official, said that because the

organization considered the outbreak to be a problem for scientists

and not something that would change global vaccination practices, they

thought it was was unnecessary to immediately share publicly.

 

CDC's Kew added: " The people who are against immunization may seize on

anything that could strengthen their position, even if it's

scientifically untenable. "

 

Rumors are still rife among Nigerians that the vaccine is unsafe, and

several religious leaders continue to lecture on its dangers. Another

mass vaccine boycott could lead to further polio spread, derailing

long-standing eradication efforts for good.

 

Nigerian health officials contacted by The Associated Press declined

to comment on the situation.

 

" Convincing the Nigerians to take even more of this vaccine will be a

tough sell, " said Dr. Samuel Katz, an infectious diseases specialist

at Duke University and co-inventor of the measles vaccine.

 

More than 10 billion polio doses have been given to children

worldwide, and the vaccine has been credited with cutting polio

incidence by more than 99 percent since 1988. Far more children are

paralyzed by the wild polio virus than the virus spread by the oral

vaccine. But no vaccine is risk-free.

 

WHO said that changing the vaccination strategy is unnecessary. " It

would be nice if we had a more stable oral polio vaccine, but that's

not the way it is today, " Heymann said. " We will continue working the

way we have been working because we don't want children to be

paralyzed anywhere. "

Link to comment
Share on other sites

Join the conversation

You are posting as a guest. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...