Showing posts with label Influenza vaccine. Show all posts
Showing posts with label Influenza vaccine. Show all posts

Sunday, November 26, 2017

ACOG updates the practice advisory for influenza vaccination during pregnancy



The American congress of obstetrics and gynecologists(ACOG) has issued a recent practice advisory for influenza vaccination during pregnancy.

A recent case -control study published in September issue of journal Vaccines linked spontaneous abortion and receipt of influenza vaccine in first trimester of pregnancy. In this case control study women had nearly twice the odds of experiencing a miscarriage if they were vaccinated in the preceding 28 days period. (OR 2.0; 95% CI 1.1–3.6)

The odds of spontaneous miscarriage were further increased 7 times if the women also received the pH1N1-containing vaccine in the previous influenza season. (OR 7.7; 95% CI 2.2–27.3)
Once the 28 days window is passed, not increased chances of spontaneous pregnancy loss was observed.

The same study also observed no adverse effects or pregnancy loss when vaccination was given either later in the first trimester or in the second or third trimester.

Hence, ACOG reviewed the evidence by evaluating all the scientific information available and concluded that this study had some limitations and does not establishes causality. It also calls for additional studies and clinical trials before the concern is fully addressed.

ACOG still affirms it stand of vaccinating every pregnant woman with a flu shot, irrespective of the trimester she is in.

For many years, ACOG and the CDC have recommended that every pregnant woman receive a flu shot during any trimester.






Monday, June 26, 2017

ACIP broadens its policy for Influenza vaccination in pregnant women and children

https://www.flickr.com/photos/31064702@N05/2988216443
The CDC’s Advisory Committee on Immunization Practices (ACIP) passed new draft recommendations for influenza vaccine in children and pregnant women.

The basic recommendations for Influenza vaccination for 2017-2018 flu season would remain the same.

A major update was allowing of any licensed, recommended and age-appropriate trivalent or quadrivalent inactivated influenza vaccine (IIV) or recombinant influenza vaccine (RIV) for pregnant women as against the previous recommendation which only specified inactivated vaccine (IIV).
Some of the committee members were uncertain about safety of recombinant influenza vaccine (RIV), Flublok.

Lisa Grohskopf, MD, MPH, medical officer of the influenza division of the CDC, did acknowledge that there were more data on the safety of inactivated influenza vaccines, she asserted to the committee that “the general overall safety profile of Flublok in comparison to inactivated vaccines is reassuring.”

In addition, the committee advised against use of quadrivalent live attenuated influenza vaccine (LAIV4), which is given by nasal spray, in the coming season because of its declining efficacy. The vaccine failed to show any statistically significant benefits in pediatric age group during last three seasons.

Also, Afluria, an inactivated influenza vaccine in both trivalent and quadrivalent formulas can now be safely administered to children aged 5 years and above instead of 9 years and above. This is because similar rates for febrile seizures and reactions were observed in both the age range.

The director of the CDC and the U.S. Department of Health and Human Services will look into the approved recommendations.  Once reviewed and approved, the final recommendations will be published in the CDC’s Morbidity and Mortality Weekly Report.





Tuesday, December 27, 2016

Maternal vaccines uptake during pregnancy remains low despite years of efforts.


 
courtesy istock. 

The development of new vaccines and the safety data now available for old vaccines ensures that more and more patients should receive the required vaccination in pregnancy. This is important in disease prevention and transfer of passive immunity to the unborn child.

The uptake of two commonly recommended influenza and the tetanus-diphtheria-acellular pertussis (Tdap) vaccine remains low despite being advised since years. The most recent national data was presented at 47thNational Immunization Conference (NIC) hosted by CDC in Atlanta, Georgia.

The data showed that Tdap vaccination coverage is only 10% in pregnancy while the influenza vaccination rate among pregnant women is about 50%, with 14% of women being vaccinated in the 6 months before pregnancy and 36% during pregnancy.

In a survey sent out by Sean O’Leary, MD, of the department of pediatrics, section of infectious diseases, at the University of Colorado, Denver and his colleagues, it was seen that only 75% of gynecologists routinely administered the Tdap vaccine, and 85% routinely administered the influenza vaccine to their pregnant patients.

Reimbursement-related issues topped the list of barriers, while lack of time during the antenatal visits, refusal by the patients and inability to maintain the stock of vaccines were other issues.

Dr O’Leary  said “Immunization delivery in the ob.gyn. setting may present different challenges than more traditional settings for adult vaccination, such as family medicine or internal medicine offices.”

Vaccines recommended for all pregnant women

The Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC) recommends a dose of Tdap during each pregnancy, irrespective of the patient’s prior history of receiving Tdap. Optimal timing for Tdap administration is between 27 weeks and 36 weeks of gestation to maximize the maternal antibody response and passive neonatal transfer.

Influenza vaccination is recommended if patient is pregnant during the flu season.

courtesy: shot of prevention 


Vaccines recommended for selected pregnant women who are at risk or  traveling to high risk areas.

Hepatitis A: The vaccine carries no known risks to the developing fetus.  
Hepatitis B: vaccine can be given in pregnancy in some circumstances. Limited data suggest that developing fetuses are not at risk for adverse events when hepatitis B vaccine is administered to pregnant women. [1]
Pneumococcus: safe if given in second and third trimester.[2]

General principles of Immunization in Pregnancy

The ACOG recommends routine assessment of immunization status of all pregnant women and administration of indicated vaccines.

Robust data and growing body of evidence demonstrate that administering inactivated virus or bacterial vaccines or toxoids is safe during pregnancy.

Live attenuated vaccines (eg, measles-mumps-rubella [MMR], varicella, and live attenuated influenza vaccine) do pose a theoretical risk (although never documented or proved) to the fetus and generally should be avoided during pregnancy.

Women who have inadvertently received immunization with live or live-attenuated vaccines during pregnancy should not be counselled to terminate the pregnancy because of a teratogenic risk.

Women who are breastfeeding can still be immunized (passive-active immunization, live or killed vaccines)





[1] https://www.cdc.gov/vaccines/pregnancy/hcp/guidelines.html
[2] http://www.uptodate.com/contents/vaccination-during-pregnancy-beyond-the-basics

Friday, April 1, 2016

Incidence of still births halved after Seasonal Trivalent Influenza Vaccination During Pregnancy: First Population-Based Retrospective Cohort Study.



The Obstetric Practice and Immunization Expert Work Group of the American College of Obstetricians and Gynecologists (ACOG) updated the committee opinion that all pregnant women should receive influenza vaccination back in 2014. World Health Organizations and CDC guidelines recommend seasonal influenza vaccinations(inactivated influenza vaccine ) for pregnant women in any trimester. However, the live attenuated vaccine is not recommended for pregnant women but can be used safely during the postnatal period.

Pregnancy puts women at increased risk pneumonia and acute respiratory illnesses because of lowered immunity. Antenatal Infections are also linked to fetal mortality and preterm labor. But, in spite of it only 50% of women get themselves immunized due to safety concerns for the fetus.

Recent research shows that there are other maternal and fetal benefits of seasonal influenza vaccination, other than just preventing the flu. A Canadian study by published in Canadian Medical Association Journal has shown that Influenza Vaccination in pregnancy reduces the odds of having a preterm delivery or delivery of a low-birth-weight baby compared with pregnant women who did not get the vaccine.

A recent Population based retrospective study by published online on March 30, 2016 in the journal of Clinical Infectious Diseases  have shown that women in western Australia who received the vaccine have half the risk of stillbirths as compared to women who do not receive the shot.

The lead author Annette K. Regan, MPH, from the School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, and Western Australia Department of Health, Shenton Park said in a news release “During the 2009 H1N1 pandemic, we saw a similar reduction in stillbirths following vaccination,” she added that “Our results are particularly exciting since they show we can get the same protection during seasonal epidemics, which occur every winter. Unfortunately, we know that about 40 percent of pregnant women go unvaccinated, missing out on these benefits.”

The researchers in Australia analyzed midwives’ data retrospectively. A total of 58,008 women delivered during the winter flu season in the year 2012 and 2013 in Western Australia. Out of which 5076 women received the influenza vaccine, and 377 stillbirths occurred. After adjusting for confounders (maternal smoking, indigenous status, and propensity for vaccination) the risk of stillbirth among vaccinated mothers was 51 percent lower than the risk among women who had not been vaccinated.

The observed rate of stillbirths also increased around the time of Influenza virus circulation, suggesting a link between the virus and stillbirths.

The authors call for further research to look into causes of decrease in still birth rates following Influenza vaccination.

"Given the growing body of evidence supporting the health benefits to mother and infant, concerted efforts are needed to improve seasonal influenza vaccine coverage among pregnant women," the researchers conclude.

The study limitations were being retrospective, depending upon data reporting by healthcare workers and generalizability of findings to women in developing countries.

The study also has wider implications on global public health level as vaccination against Influenza is an attainable step to avert stillbirths. In 2015, an estimated 2·6 million (uncertainty range 2·4–3·0 million) babies were stillborn, with 70% of infant death around the time of birth.



References:
http://cid.oxfordjournals.org/content/early/2016/03/10/cid.ciw082.abstract