When the vaginal microbiome gets out of whack, it causes an uncomfortable, often chronic condition known as bacterial vaginosis, which is associated with pregnancy complications such as premature birth as well as a heightened risk of contracting sexually transmitted diseases. But finding ways to return the disrupted vaginal microbiome to its normal, healthy state has proven difficult because nobody knows what ‘normal’ really means.

As Nature Medicine reported in a July 2011 news feature, a team of scientists at the University of Maryland School of Medicine in Baltimore had found that there are many naturally occurring versions of the microbiome, in part because the bacteria present in a woman’s vagina may vary according to her ethnicity. In a paper published today in the journal Science Translational Medicine, the same team goes on to show that although ethnicity can predict the make up of a the vaginal microbiome over a lifetime, in individual women this bacterial community can change dramatically within a matter of days—often without causing any effects on health.

To characterize this microbial variability, the scientists recruited 32 healthy volunteers for a labor-intensive study. The women enrolled, half of whom were black and half of whom were white, self-sampled vaginal swabs twice a week for more than three months and sent them off to the lab of lead author Jacques Ravel and his collaborator, Larry Forney of the University of Idaho in Moscow. There, biologists sequenced the genomes of the bacteria present in the samples to determine the relative abundance of, for example, the common bacteria species Lactobaccilus or Anaerococcus. For each woman, a picture emerged of a unique and surprisingly mercurial bacterial community. “There has been an assumption that microbiomes are stable over time,” says Forney. “But we found that over the course of just a few days, the entire microbial community could change in a given woman.”

These findings could help biologists develop personalized treatments for bacterial vaginosis, yeast infections and other conditions in which the microbiome is disturbed. “Right now, the antibiotic and probiotic treatments that exist for these diseases work for some women but not for others, and that’s because we don’t understand the environment we’re trying to treat,” says Forney. The hope, he and his colleagues say, is that these findings will lead to new treatments tailored to specific groups of women.

To move toward that goal, they have already begun enrolling more than 160 women to take daily vaginal samples for a larger, more rigorous study of how the various ‘normal’ microbiomes they identified in today’s paper change when a healthy woman develops a vaginal infection. “We need to start rethinking the idea of personalized treatment for diseases of the vagina,” says Ravel.

To read ‘The Vagina Catalogues’ click here.

Artwork by Alyssa Grenning

The Affordable Care Act contraceptive coverage currently being debated in the US Congress could allow institutions that provide health insurance to opt-out of covering birth control pills for religious or moral reasons. Such policies have, in the past, raised difficulties for women prescribed the drugs for noncontraceptive uses, such as the treatment of pain from ovarian cysts. On 23 February, a law student at Georgetown University named Sandra Fluke testified before the US House Committee on Oversight and Government Reform that when insurance coverage doesn’t cover contraceptives, it can deny women such a friend of Fluke’s with polycystic ovarian syndrome access to birth control prescribed to treat the condition. And although such treatments do not cure the underlying causes of such conditions—oral contraceptives do not shrink ovarian cysts—there is accumulating evidence that they can be used as analgesics, allowing women to avoid invasive surgeries to remove abnormal tissue from the uterus or ovaries. The debate over limiting coverage by private insurance for contraceptives raises the question of whether denying access will cause real, physical pain to women in the US.

Prescription for pain from ovarian cysts is just one of many noncontraceptive uses of popular combination hormonal birth control pills such as Yaz, Orthocept and Ortho Novum, which prevent pregnancy by suppressing ovulation or blocking proliferation of the endometrial lining of the uterus, deterring implantation of an egg. “Birth control is also a widely prescribed treatment for pain from endometriosis and fibroid tumors in the uterus,” says Joyce King, a nurse at Emory University in Atlanta who studies the benefits of contraceptives.

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Texas Governor Rick Perry has taken a lot of flak for mandating that adolescent girls in the Lone Star State should be vaccinated against the human pappilomavirus (HPV). But Perry’s policy might have a strong scientific grounding. According to a report published today in PLoS Medicine, blanket vaccinating young girls might be the most effective way of curbing the cancer-causing virus.

A team led by Johannes Bogaards, a biostatistician at the VU University Medical Centre in the Netherlands, devised a mathematical model of sexually transmitted infections to investigate whether vaccinating males only, females only or both sexes was the best way to reduce the prevalence of such diseases. The researchers found that single-sex vaccination was most effective, and that the sex vaccinated should be the one with the highest prevalence of the disease.

Since HPV is more common among girls than boys, “vaccinating additional females is more effective in blocking transmission and reducing the population prevalence of infection than it is to start vaccinating males,” Bogaards says.

That conclusion runs counter to recent policy recommendations made by the US Centers for Disease Control and Prevention (CDC). In October, the agency recommended that young boys should be vaccinated alongside their female schoolmates to help stem the transmission of the virus.

Despite the Dutch team’s analysis, however, Joseph Bocchini, chairman of the CDC advisory committee on HPV, stands by his agency’s recommendations. He notes that sociopolitical stigma and misinformation have led to low vaccination rates in the US that upset many of the assumptions of the Dutch model. As such, he explains, “the fewer women who are immunized the more we stand to gain from vaccinating boys.”

The mathematical model also assumes only heterosexual disease transmission, notes pediatrician Luis Barroso of Wake Forest University in North Carolina. The analysis “doesn’t take into account men having sex with men,” who would get “no protection at all from vaccinating women,” he says. That’s why, in addition to adolescent boys, the CDC’s October report recommended vaccination for men up to age 26 if they have sex with other men.

Such disagreements within the scientific community reflect the difficulty of creating an epidemiological model that can be widely applied. One thing epidemiologists, biostaticians and policymakers all agree on is that the HPV vaccine is safe, effective and should be widely implemented. Convincing parents of that fact is proving to be the most difficult obstacle to overcome.

Yesterday, the New York Times reported that while items like acne creams and denture adhesive are eligible for tax breaks under the new US health care law, breast pumps are not. Breast-feeding boosters like La Leche League are, naturally, up in arms, but the US Internal Revenue Service says that the pumps do not fall under the umbrella of preventative medicine, since breast milk is primarily nutrition.

To counter the IRS, breast-feeding advocates point to research showing that breast-feeding transfers essential antibodies from mother to child. There’s also research suggesting that bacteria in mother’s milk plays a key role in building up a healthy community of intestinal microflora.

But in certain circumstances, breast-feeding can be a vector for harmful microbes as well. In February, the US Centers for Disease Control (CDC) reported the case of a mother in Brazil who, after she received a yellow fever vaccine, passed the virus to her infant through her milk. Hepatitis B virus (HBV) has been detected in the milk of HBV-positive mothers, though it’s unclear if the virus can actually be transmitted through breast-feeding; the most common method of mother-to-child HBV transmission is during delivery itself. If a Hepatitis C-positive mother has cracked or bleeding nipples, she runs a higher risk of transmitting the virus to her infant. UNICEF estimates that if an HIV-positive mother breast-feeds, she’ll pass the virus to her child 5 – 20% of the time.

It’s worth noting that another US government agency, the Transportation Security Administration, classifies breast milk as ‘liquid medication’, which is why mothers are allowed to bring more than three ounces of it on a plane.

Image by planet _oleary via Flickr Creative Commons

This time of year, the leaves are turning red and yellow and orange, but just about everything else is blushing pink. That’s right: it’s Breast Cancer Awareness Month! The Susan G. Komen for the Cure Foundation has raised more than $1.5 billion for breast cancer research since it started in 1982, and $55 million a year comes from corporate marketing partnerships (including the special edition KFC bucket). We’ve covered these questionable ‘pinkwashing’ practices before. And this October, there’s a new wrinkle to breast cancer activism: half-hearted online awareness campaigns.

The iconic pink ribbon debuted in the early 1990s, and was popularized after the Komen Foundation handed ribbons out to participants in the 1991 Race For the Cure in New York City. Corporations soon discovered that affixing the symbol on their product not only helped their image, but their profit margin as well. In 2006, Campbell’s Soup saw its sales double when it offered pink versions of its iconic cans. In exchange, the company donated $250,000, or a mere 3.5 cents per pink can, to the Susan G. Komen Foundation. When it comes to buying pink products, it’s important to read the fine print: a company may have a cap on the amount of money it’ll donate, and some do not specify what organization the donations are going towards.

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