UPDATE 3-Dutch pull Pfizer vaccine batch after infants die

* 3 deaths in October after Prevenar vaccination

* Cause of deaths to be determined-Dutch health authority

* Suspended batch contains 110,000 doses (Adds details on vaccine)

AMSTERDAM, Nov 5 (Reuters) - Dutch authorities say they have banned use of a batch of Pfizer Inc's (PFE.N) Prevenar, or Prevnar, after three infants died within two weeks of receiving the anti-infection vaccination.

"On average about 5 to 10 deaths are reported annually after babies get vaccines," said a spokeswoman for the Dutch health institute RIVM.

"We now have three cases in a short period; that is unusual, and the reason for suspending the batch."

She said RIVM is investigating the cause of the infants' deaths. Other batches of Prevenar, known as Prevnar in the United States, will continue to be used.

Pfizer spokeswoman Gwen Fisher said preliminary investigations by the company and health authorities had found no link between the vaccinations and the deaths.

She said the company initiated the "quarantine" of the batch, which she said contained 110,000 doses of Prevenar, used to prevent pneumonia and related infections.

Fisher said the three infants also received two unrelated other vaccines as part of routine immunizations.

No other Prevenar batches were suspended, and infants in the Netherlands will continue to be vaccinated with it as part of routine immunization, she added.

A spokesman for the European Medicines Agency in London said its officials are working with the Dutch authorities to find out whether there were any safety issues with the vaccine batch.

The vaccine is one of the most widely used in the world and generated sales for U.S. drugmaker Wyeth of $2.7 billion in 2008.

Wyeth, which has just been acquired by U.S. rival Pfizer, had asked for the suspension of batch D66977 of Prevenar, RIVM said in a statement.

Pfizer is awaiting U.S. approval of a new form of the vaccine, called Prevnar 13, that would protect against additional strains of a bacterium called streptococcus pneumoniae that can cause an array of diseases, ranging from ear infections to pneumonia and meningitis.

Pfizer hopes to eventually seek approval of Prevnar 13 for adults, a new market that could ensure continued strong sales growth of the Prevnar franchise for years to come.

In late New York Stock Exchange trading, Pfizer shares were up 7 cents to $17.00. (Reporting by Gilbert Kreijger, with additional reporting by Ben Hirschler in London and Ransdell Pierson in New York; editing by Simon Jessop, David Cowell and Gerald E. McCormick)