Vaccine

It's the latest start for a flu season in 29 years, and thus far, severe cases have been few. But that doesn't necessarily mean Americans have dodged any seasonal illness bullets. Influenza is just beginning to gain a foothold around the country.  "The flu season has officially begun," Dr. Joseph Bresee told reporters Friday morning during a briefing at the agency's headquarters in Atlanta. Infections have reached all 50 states, said Bresee, who is chief of the epidemiology prevention branch at the U.S. Centers for Disease Control's influenza division.

Facing an epidemic of whooping cough that led to the deaths of 10 infants in 2010, California public health officials launched a massive vaccination effort and public awareness campaign about the disease. And on Tuesday, they announced the payoff: no deaths in 2011, a first in two decades. The number of whooping cough, or pertussis, cases also plummeted from about 9,154 in 2010 to 2,795 in 2011, according to the California Department of Public Health. In Los Angeles County, the number of cases dropped from 1,395 in 2010 to 520 in 2011.

Exposure to perfluorinated compounds, or PFCs, a class of chemical used in food packaging and textiles, was associated with a lowered immune response to the tetanus and diphtheria vaccines in 5- to 7-year-olds in the Faroe Islands, researchers reported Tuesday in the journal JAMA. The scientists followed close to 600 children from the islands, which are in the Norwegian Sea north of Scotland and are a self-governing part of the Kingdom of Denmark, because people there eat a lot of seafood.  A marine-based diet is associated with increased exposures to PFCs, according to background information in the JAMA report.

International aid groups say they're under siege in Pakistan, demonized by hard-line Islamists, viewed as spies by suspicious Pakistanis and, now, increasingly sidelined by the government. The groups report that in the last year, they began to feel unwanted in the country, and in some cases persecuted. Nongovernmental organization visa requests languished or were outright rejected. New travel restrictions hampered aid workers' movement. Some workers were arrested and harassed. Western aid officials believe that the Pakistani government's suspicions about the groups rose dramatically last year after the U.S. commando raid that killed Osama bin Laden in May in the military city of Abbottabad.

Some girls may be more likely to overestimate the protection they receive from the HPV vaccine, new research shows. Human papillomaviris, the most common sexually transmitted infection, can infect the genital areas of men and women, cause genital warts and raise the risk of cervical cancer. The new study, published this week by the Archives of Pediatrics and Adolescent Medicine, looked at the perception of HPV risk among a population of 339 girls between age 13 and 21. At an average age of 16.8 years, 57.5% of these girls were sexually experienced, and most of them reported "continued need" to practice safe sex. However, a good 23.6% appeared to believe mistakenly that their risk of other sexually transmitted diseases was also lower -- even though the HPV vaccine does not protect against the rest of the pantheon of such diseases, such as HIV/AIDS, gonorrhea and syphilis.

Finding a vaccine to stop herpes has been frustrating for researchers. The family of herpes viruses inflict suffering on millions of people. Herpes simplex virus type 1 is generally linked to fever blisters and genital herpes and type 2 causes genital sores. A study published Wednesday shows progress toward a vaccine but hardly perfection. Researchers evaluated 8,323 women ages 18 to 30 who were not infected with either virus. Almost 3,800 of the study participants received an experimental vaccine known as glycoprotein D. Previous studies suggested the vaccine could be effective against herpes type 2. But after 20 months of follow-up, the new study found the vaccine was partially effective in preventing herpes type 1 (after two or three doses)

Vaccination against human papilloma virus was recommended for U.S. girls almost five years ago. In October, a government advisory committee also recommended routine vaccination for boys ages 11 and 12.   But vaccinating girls only makes the most sense, researchers said Tuesday. Using mathematical models, researchers in the Netherlands found vaccinating girls is the best way to reduce heterosexual transmission because girls have the highest prevalence of the virus. Immunizing the group with the highest prevalence achieves the largest population-wide reduction of the virus.

Vaccinating children who are more than a year old against varicella, or chicken pox, also provides "tremendous indirect benefits" to young babies, researchers reported Monday in the journal Pediatrics. The U.S. implemented a variella vaccine program in 1995, offering the vaccine to children 12 months and older.  But younger babies who aren't old enough to get the vaccine are protected through so-called "herd immunity" -- because fewer older kids develop chicken pox, the younger children are less likely to be exposed to the virus.

The vaccine wars have moved to higher ground: the cabins of Delta airplanes. A leading group of pediatricians has warned Delta Air Lines that an ad being aired on some of its flights is "putting the lives of children at risk, leaving them unprotected from vaccine-preventable diseases. " The ad, sponsored by the National Vaccine Information Center, focuses on such preventive measures as handwashing and tells viewers to question "vaccines your doctor may recommend" -- with some serious emphasis on the "may.

Monthly shots of a cancer vaccine produced encouraging results in a small, very early trial of 26 women with metastatic breast or ovarian cancer (cancer that has spread to other sites around the body), most of whom already had had three or more rounds of chemotherapy. Among the 12 breast cancer patients, median survival time was 13.7 months and one patient was still alive at 37 months, when the paper was written up. Four remained stable during the course of the trial. Among the 14 ovarian cancer patients, median survival was 15 months.