The California Department of Public Health (CDPH) is reporting an uptick in cases of pertussis since the beginning of the year. According to the state, a total of 2,649 cases have been reported, with more than 800 new cases reported in April alone—the highest monthly count since the 2010 epidemic.

Pertussis can cause serious and sometimes life-threatening complications in infants, especially within the first 6 months of life.Two infant mortalities have been reported this year—the first infant pertussis fatalities reported since 2010. In 2010, 9,159 total cases were reported, including 10 deaths — all infants.  So far this year 77 children have been hospitalized, most of these younger than three months. Ninety percent of the cases have been in children under the age of 18, with 32 percent of them ages 14 to 16.

State public health officials remind physicians that the best way to protect infants against fatal or severe pertussis infection is to vaccinate pregnant women with Tdap during every pregnancy. Vaccinated pregnant women develop antibodies to pertussis that are passed to the fetus and may protect young infants until they are old enough to be vaccinated at six weeks of age. To maximize the maternal antibody response and passive antibody transfer to the infant, optimal timing for Tdap administration is between 27 and 36 weeks of gestation. In addition to providing pertussis antibodies to the infant, the mother herself will be protected and less likely to become infected and transmit pertussis to her infant.

Vaccination during pregnancy is highly preferred over postpartum vaccination. However, if a woman is not vaccinated prior to giving birth, it is recommended that she receive the vaccine before hospital discharge (breastfeeding is not a contraindication).

Other family members and close contacts of infants who have not received Tdap, should be vaccinated at least 2 weeks prior to any contact with the infant.

It is recommended that babies get their first dose of the pertussis vaccine at 2 months of age, and should have three doses by the time they are 6 months old. Children should also receive booster shot in their second year, before kindergarten and at 11-12 years of age. Adults and teens who never received a vaccine during their preteen years are also encouraged to get vaccinated.

For more information and guidelines on pertussis vaccination, see the California Department of Public Health website.