poliomyelitis spreads in west and central africa

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THE LANCET Neurology Vol 3 March 2004 http://neurology.thelancet.com136

Newsdesk

On Jan 27, WHO confirmed a case ofparalytic poliomyelitis in CentralAfrican Republic, the seventh polio-freecountry to report a case caused by apoliovirus imported from Nigeria.However, Nigeria’s northern Kano statewarned on Jan 19 that it would onlyrelaunch a poliomyelitis vaccina-tion campaign if its fears aboutthe vaccine’s safety areaddressed.

Kano state’s spokespersonSule Yau Sule told journaliststhat Kano scientists have foundcontaminants in the vaccine.“This is really bad news becausewithout Kano’s support, trans-mission will not be stopped”,says UNICEF’s spokespersonClaire Hajaj.

In Oct, 2003, Kano and twoother northern states—Zamfaraand Kaduna—suspended their polio-myelitis vaccination programmesbecause the country’s SupremeCouncil for Sharia was concerned thatthe vaccine contained HIV andsubstances that could affect fertility. Asa result, poliomyelitis virus from thenorth has infected children inpreviously disease-free states within

Nigeria, as well as Benin (one case),Burkina Faso (seven cases), Cameroon(one case), Central African Republic(one case), Chad (five cases), Ghana(eight cases), and Togo (one case).

The announcement from Kanostate came only 4 days after represent-

atives from Nigeria, Pakistan, India,Afghanistan, Egypt, and Niger signedthe Geneva Declaration for the Eradica-tion Of Poliomyelitis. Nigeria pledgedto increase substantially immunisationrates in the northern states during thefirst half of 2004.

WHO’s spokesperson MelissaCorkum says that the spread has

necessitated a massive US$20 millionimmunisation campaign across westand central Africa at a time when thepoliomyelitis eradication initiative isfacing a US$150 million funding gap.“The risk of importations into west andcentral African countries, and around

the world, is magnified by thefunding gap, which limits thescope of immunisation activities”,she says.

Meanwhile heavy rains haveadversely affected the latestnational immunisation days. “Of the six priority countries,Pakistan is unique in that poliotransmission in Pakistan has notbeen restricted to certain areas—it is across the country”, Hajajwarned. Tariq Iqbal Bhutta,chairman of Pakistan’s NationalPolio Eradication Certification

Committee, explained that the routineimmunisation rates are very low, whichis why the country could not eradicatepoliomyelitis despite holding manyimmunisation days. “To overcome thisproblem, it is essential that politicians atthe district and tehsil levels become fullyinvolved in this activity”, he says.Khabir Ahmad

Poliomyelitis spreads in west and central Africa

Fetal oligodendrocyte progenitor cells lose the remyelination raceOligodendrocyte progenitor cells(OPCs) isolated from the human braincan produce myelin when transplantedinto the brains of newborn congenitallydysmyelinated shiverer mice. “Theresults are much better than weexpected”, says lead investigator StevenA Goldman (Columbia UniversityMedicial School, NY, USA). “Thepercentage of cells in this experimentthat began producing myelin isextraordinary, probably thousands oftimes as many as in previousexperiments.”

Goldman and co-workers extractedOPCs from 21 to 23-week-old fetalhuman forebrain and from adultsubcortical white matter obtainedduring surgery and transplanted theminto the forebrains of newborn shiverer

mice. They found that the fetal OPCsdispersed throughout the white matterand remyelinated the rat forebrainwithin 12 weeks of transplantation.Surprisingly, OPCs derived from adulthuman white matter remyelinated the forebrain within 4 weeks oftransplantation—much quicker thanthe fetal OPCs (Nat Med 2004; 10:93–97). “The adult-acquired cells notonly myelinate much more quickly, but more extensively—they myelinatemany more axons per cell, and they doso with much higher efficiency. Theadult cells were far more efficient thanfetal cells at getting the job done”,Goldman told The Lancet Neurology.

The fact that adult cells did betterthan fetal cells could have importantimplications for autologous trans-

plantation, comments GianvitoMartino (San Raffaele Hospital,Milan, Italy). However, Martinocautions that many transplantablecells would be required to do any kindof transplant in human beings—andGoldman’s team do not show that theOPCs can be expanded in vitro. Inaddition, Martino suggests that thedifference between newborn mice andimmune-competent adult mammalsmeans that the results may nottranslate well to the clinic.

“The work is interesting from a biological point of view”, saysMartino, “but it is difficult to envisageany applicability of this myelin-repairapproach into human beings in thenear future.”James Butcher

NIGERIA

BURKINAFASO

GHANA

TOGO

BENIN

CAMEROON

CHAD

CENTRALAFRICAN

REPUBLIC

Poliomyelitis has spread from Nigeria to surrounding countries