Whooping Cough Came Back: How Vaccination in Pregnancy Shields Newborn Babies

What studies from the Netherlands, six Gulf countries, northern Italy and southern Thailand tell families about the recent outbreaks

Whooping cough came back strongly after the COVID-19 pandemic, and the babies hit hardest were only a few weeks old, too young for their own vaccines. New studies from Europe, the Gulf region and Asia show that when mothers are vaccinated during pregnancy, their newborns are far better protected, but many mothers are still missing that vaccine.

Whooping cough, known to doctors as pertussis, is a bacterial infection of the airways. For most older children and adults it is an exhausting cough that lingers for weeks. For a newborn it can be life-threatening, because tiny airways block easily and very young babies sometimes simply stop breathing instead of coughing. This article explains what four recent studies found, how they fit together, and what families can do.

Four studies telling one story

The four studies looked at the same wave of whooping cough, which picked up in 2023 and peaked in 2024, from different angles. The first, from the Netherlands, used the country's national record of every reported case from 2012 to 2024, kept by its National Institute for Public Health and the Environment, to measure how big the outbreak was and how well vaccines worked [1]. The second, called the Gulf Pediatric Pertussis Study (GPPS), gathered information on every child with confirmed whooping cough admitted to one of 35 paediatric intensive care units (PICUs), the hospital wards for the sickest children, in six Gulf countries including Saudi Arabia and Kuwait, between July 2022 and December 2024 [2]. The third followed about 107,000 mother–baby pairs with births in 2018–2022 in Lombardy, a region of northern Italy, to see whether a vaccine given in pregnancy kept babies out of hospital [3]. The fourth, from Narathiwat Province in southern Thailand, compared babies in their first 3 months who caught whooping cough during an outbreak from September 2023 to October 2024 with healthy babies from the same communities [4]. We could read only a short summary of the Thai study, not the full paper, so its result should be seen as early and encouraging rather than final. All four point in the same direction.

Why newborns are so vulnerable, and how protection in pregnancy began

Doctors have long known that the youngest babies suffer most from whooping cough. A leading expert described how these babies can look surprisingly well between frightening spells of stopped breathing or turning blue, and how the infection usually comes from a family member who did not realise their cough was whooping cough [5]. Babies get their own whooping cough vaccines starting at around 2 to 3 months of age, but it takes several doses to build full protection. That leaves a dangerous gap in the first weeks of life.

In 2012, during a large outbreak, England began offering pregnant women a booster vaccine called Tdap, which protects against tetanus, diphtheria and pertussis. The idea is simple: the mother's body makes protective antibodies, and these cross the placenta to the baby before birth, like a parent packing an umbrella in a child's bag before sending them out into the rain. It worked. Babies whose mothers were vaccinated were about 91% less likely to catch whooping cough in their first 3 months [6], and three years later protection was still above 90%, including strong protection against death [7]. A large review of 22 studies found similar protection and did not link the vaccine to problems such as early birth [8]. Dutch research added two cautions: babies born early were more often admitted to hospital with whooping cough [9], and vaccinating at 20–24 weeks of pregnancy left babies with lower antibody levels at 2 months than vaccinating at 30–33 weeks, and babies born early had lower levels too, although doctors do not yet know exactly what antibody level is enough to protect a baby, so what this means in practice is still uncertain [10].

Then came the pandemic. With masks, distancing and closed schools, whooping cough nearly vanished worldwide, and when life reopened, large outbreaks followed in many countries [11]. Dutch researchers found that protection in school-age children had faded, and that most people who caught the infection did not have a long cough, so it spread quietly [12].

How big the outbreak was

In the Netherlands, only 79 cases were reported in 2021. In 2024 there were 18,208, the most since the country started counting in 1976 [1]. Babies under 6 months were hit hardest, and roughly half of the reported babies that age (250 out of 471) needed a hospital stay. Ten people died in 2023 and 2024, five of them babies younger than 6 months.

What happened to the sickest children

The Gulf study shows what critical whooping cough looks like. Among 204 children in intensive care, the typical child was just 53 days old, and 9 out of 10 had been healthy before [2]. Only about 1 in 11 had the famous "whoop". Apart from coughing, the most common signs recorded were turning blue and vomiting, and about 3 in 10 children had pauses in breathing. About 1 in 3 needed a breathing machine. More than a quarter received a procedure to remove excess white blood cells from the blood, because the infection can push these cells to very high levels [13]. In about 1 in 4 children who had a heart scan, doctors found high pressure in the blood vessels of the lungs, a serious complication that makes it hard for the heart to pump blood through them. Sadly, 31 of the 204 children died, roughly 1 in 7, a toll similar to that seen in British intensive care units during the same period [14].

Two further findings stand out. About 6 in 10 children whose family details were recorded had someone at home who also had whooping cough. And only 4 of the 97 mothers whose vaccination history was known had received the vaccine in pregnancy [2]. That study did not compare vaccinated and unvaccinated families, so it cannot tell us on its own how well the vaccine works, but the pattern is striking.

How well the vaccine in pregnancy protects

The researchers used different methods to measure protection, which makes their agreement more convincing. The Dutch team compared how many sick babies had vaccinated mothers with how many mothers in the whole country were vaccinated; if the vaccine did nothing, the two shares would be about the same. The Italian team paired each baby of a vaccinated mother with a similar baby, born in the same month and after the same length of pregnancy, whose mother was not vaccinated, and then counted hospital visits in each group. The Thai team started with sick babies and asked how often their mothers had been vaccinated, compared with healthy neighbours. Each method has weak spots, but together they are hard to dismiss.

Here is what they found. In the Netherlands, babies aged 0–2 months whose mothers had the vaccine in pregnancy were about 91% less likely to be reported with whooping cough, and about 90% less likely to be admitted to hospital [1]. To picture it, if 10 babies of unvaccinated mothers caught the infection, only about 1 comparable baby of a vaccinated mother would. In Italy, babies of vaccinated mothers were about 89% less likely to need a hospital stay or emergency visit for whooping cough in their first 6 months [3]. Because such visits were rare, that estimate is less precise, but it agrees with the Dutch result. The Thai summary reports about 95% protection from a newer type of vaccine [4].

The missing piece: too few mothers vaccinated

The vaccine works; the problem is reach. Only 41% of eligible mothers in the Italian study were vaccinated [3], and about two-thirds of Dutch mothers were [1]. In 2024, more than 8 in 10 Dutch babies aged 0–2 months who caught whooping cough had mothers who had not been vaccinated [1].

No vaccine is perfect. Two Dutch babies who died had mothers vaccinated at 25–27 weeks of pregnancy [1], a reminder that timing may matter and that babies still need their own vaccines on schedule. Some parents also wonder whether the mother's antibodies weaken the baby's own vaccines later. Researchers have studied this, and they expect vaccination in pregnancy to keep protecting babies well [15].

What families can do

The most important step is simple: talk with your midwife, obstetrician or family doctor about the whooping cough vaccine in every pregnancy, even if you had it last time. Keep your baby's own vaccination appointments. Because most babies catch whooping cough at home [5], older children and adults who live with a newborn can ask their own doctor whether their vaccinations are up to date, and it is sensible for anyone with a lasting cough to get checked before spending time close to a young baby. If a young baby has pauses in breathing, turns blue or grey, or has coughing fits followed by vomiting, seek medical care urgently, even without a whoop. Families interested in a similar approach against another serious infant illness may like our article on vaccination in pregnancy against respiratory syncytial virus.

What researchers are working on next

Scientists want to learn the best week of pregnancy for vaccination, especially for babies who may be born early [10]. They are also looking for a blood test that shows exactly how much antibody is enough to protect a baby, and experts have called for newer whooping cough vaccines [11]. The Gulf intensive care doctors have called for shared treatment plans so that every sick baby receives the same high standard of care [2].

Bringing it together

These studies describe one outbreak from four directions. Whooping cough returned with force after the pandemic, it was most dangerous for babies only weeks old, and vaccination in pregnancy protected those babies remarkably well. The main challenge now is making sure that every pregnant woman is offered the vaccine and has the chance to talk it through.

References

  1. van Roon A, van Meijeren D, de Gier B, et al. Surveillance and vaccine effectiveness of pertussis, the Netherlands, 2012 to 2024, with an unprecedented surge in 2023 and 2024. Euro Surveill. 2026;31(15):2500919. doi:10.2807/1560-7917.ES.2026.31.15.2500919 ↩
  2. Alghounaim M, Shaheen NA, Aldaithan A, et al. Critical pertussis in the PICU: multinational study in the Gulf Cooperation Council region, 2022–2024. Pediatr Crit Care Med. 2026;27(9):1106-1115. doi:10.1097/PCC.0000000000003956 ↩
  3. Morabito G, Corrao G, Giaquinto C, et al. Maternal vaccine receipt and infant hospital and emergency visits for influenza and pertussis. JAMA Netw Open. 2026;9(1):e2553179. doi:10.1001/jamanetworkopen.2025.53179 ↩
  4. Phiriyasart F, Chongsuvivatwong V, Kumwichar P. Real-world effectiveness of maternal genetically inactivated acellular pertussis vaccination in protecting infants under three months of age: a case-control study using concurrent community-based and test-negative controls. Infection. 2026. doi:10.1007/s15010-026-02868-x ↩
  5. Cherry JD. Pertussis in young infants throughout the world. Clin Infect Dis. 2016;63(suppl 4):S119-S122. doi:10.1093/cid/ciw550 ↩
  6. Amirthalingam G, Andrews N, Campbell H, et al. Effectiveness of maternal pertussis vaccination in England: an observational study. Lancet. 2014;384(9953):1521-1528. doi:10.1016/S0140-6736(14)60686-360686-3) ↩
  7. Amirthalingam G, Campbell H, Ribeiro S, et al. Sustained effectiveness of the maternal pertussis immunization program in England 3 years following introduction. Clin Infect Dis. 2016;63(suppl 4):S236-S243. doi:10.1093/cid/ciw559 ↩
  8. Vygen-Bonnet S, Hellenbrand W, Garbe E, et al. Safety and effectiveness of acellular pertussis vaccination during pregnancy: a systematic review. BMC Infect Dis. 2020;20(1):136. doi:10.1186/s12879-020-4824-3 ↩
  9. van der Maas NAT, Sanders EAM, Versteegh FGA, et al. Pertussis hospitalizations among term and preterm infants: clinical course and vaccine effectiveness. BMC Infect Dis. 2019;19(1):919. doi:10.1186/s12879-019-4563-5 ↩
  10. Immink MM, Bekker MN, de Melker HE, et al. Maternal pertussis immunization and immunoglobulin G levels in early- to late-term and preterm infants. JAMA Netw Open. 2024;7(7):e2424608. doi:10.1001/jamanetworkopen.2024.24608 ↩
  11. Gorringe A, Cavell B, Beard F, et al. Global incidence of pertussis after the COVID-19 pandemic. JAMA Netw Open. 2025;8(12):e2545963. doi:10.1001/jamanetworkopen.2025.45963 ↩
  12. Gaasbeek CM, Vos ERA, van Roon AM, et al. Antibody waning and Bordetella pertussis resurgence after the COVID-19 pandemic in the Netherlands. Nat Commun. 2026;17(1):2989. doi:10.1038/s41467-026-69885-0 ↩
  13. Carbonetti NH. Pertussis leukocytosis: mechanisms, clinical relevance and treatment. Pathog Dis. 2016;74(7):ftw087. doi:10.1093/femspd/ftw087 ↩
  14. Calley J, Agbeko R, Day E, et al. Characteristics and outcomes of children admitted to paediatric intensive care units with life-threatening pertussis infection in Great Britain 2023-2024. Arch Dis Child. 2025;110(12):1003-1007. doi:10.1136/archdischild-2025-328783 ↩
  15. Briga M, Goult E, Brett TS, et al. Maternal pertussis immunization and the blunting of routine vaccine effectiveness: a meta-analysis and modeling study. Nat Commun. 2024;15(1):921. doi:10.1038/s41467-024-44943-7 ↩