Vaccines

Large-scale tests of AIDS vaccines in uninfected volunteers may begin in two to four years and specialized tests to determine if the vaccines can protect the unborn fetuses of infected pregnant women could begin in 1991, leading vaccine researchers predicted Friday at the international AIDS conference here.

Last week, the U.S. Court of Federal Claims began hearing arguments about whether a childhood vaccine that protects against measles, mumps and rubella caused autism in a 12-year-old (Cedillo versus Secretary of Health and Human Services). Here is a look at the studies behind the controversy. In 1998, a gastroenterologist named Dr. Andrew Wakefield, then at the Royal Free Medical School in London, examined 12 children with bowel problems.

Each year, malaria kills more than 1 million people -- 90% of them in sub-Saharan Africa and 80% of them younger than 5 -- and makes 300 million people seriously ill. Major progress in controlling the disease has been made by the widespread adoption of bed nets to keep mosquitoes from attacking children at night and by the use of artemisinin-based therapy, which is the most effective treatment for infections. But vaccines have historically proved the best technique for controlling infectious diseases, and researchers have high hopes for a new one called RTS,S/AS2A, or Mosquirix.

The United States' supply of vaccine for the impending flu season took a hit Thursday when Chiron Corp. said it had found tainted doses in its factory. Chiron said it would delay shipment of nearly 50 million shots -- about half the supply health officials had hoped to have on hand this year. Chief Executive Howard Pien said the company hoped to ship 46 million to 48 million doses by early October, about a month later than usual, pending the results of an internal investigation.

In years past, the nation's attempts to prevent flu-related deaths have focused on limiting transmission of the virus through widespread vaccination programs. This year, with school starting up well before a vaccine for the pandemic H1N1 influenza virus will be available, there will be little that can slow the spread of the virus for the next few months.

Texas on Friday became the first state to require school-age girls to be vaccinated against a sexually transmitted virus that has been shown to cause cervical cancer. Gov. Rick Perry signed an executive order mandating that most girls, starting in September 2008, receive the vaccination against the human papillomavirus before entering sixth grade. More than a dozen states, including California, have been considering such a move.

At least 25 public health agencies have received less than the state average of 45% of their order of H1N1 flu vaccines due to distribution problems, state officials said Wednesday. "It was supposed to be a short-term problem, but it has stretched out," said Mike Sicilia, spokesman for the state Department of Public Health. Federal officials bought the vaccines and contracted with a division of San Francisco-based McKesson Corp. to distribute them nationally. Some county agencies received as little as 31% of the vaccines they ordered.

One immediate effect of the declaration of an H1N1 flu pandemic will be to speed the production of a vaccine against the new virus, but it will be fall at the earliest before the first doses are available. Scientists have encountered some problems in paving the way for such a vaccine. The H1N1 virus grows more slowly in eggs than the seasonal flu virus does, so it has taken longer than expected to prepare the seed stocks of virus that manufacturers will use to start production.

An experimental malaria vaccine protected 65% of Mozambique infants who received a full course of injections, paving the way for a large clinical trial of what could be the first vaccine against the deadly disease, researchers reported Wednesday. Infants are among the most vulnerable to malaria. Immunization of infants has proved difficult for a variety of illnesses, including measles and pneumococcal disease.

Vaccine maker MedImmune has voluntarily recalled 13 lots of vaccine against the pandemic H1N1 influenza because they have lost some potency since they were manufactured, the company said Tuesday. "This is not a safety issue," Norman Baylor, director of the Office of Vaccines Research and Review at the Food and Drug Administration, said in a conference call. "All lots passed pre-release testing for safety, purity and potency. There has just been a slight decrease in potency." The 13 lots recalled involved 4.7 million doses of the intranasal vaccine, which is based on a live, weakened virus, but officials believe most of them were administered in October and November when the product would have still been at full potency.