[Epidemiological characteristics and clinical manifestations of adult pertussis in Zhejiang Province, 2024].

Objective

To systematically describe and analyze the epidemiological characteristics and clinical manifestations of adult pertussis in Zhejiang Province in 2024.

Methods

Data on pertussis cases reported in 2024 among individuals aged≥18 years residing in Zhejiang Province were collected from the China Disease Control and Prevention Information System. Additional clinical and hospitalization information was obtained through a specialized survey. Descriptive analysis was conducted on epidemiological and clinical characteristics.

Results

In 2024, a total of 3 994 adult pertussis cases were reported in Zhejiang Province, accounting for 6.67% of all pertussis cases (59 917), with a reported incidence rate of 7.14 per 100 000. Female cases (2 541, 63.62%) outnumbered male cases (1 453, 36.38%). The majority of cases were aged 30-39 years (1 598, 40.01%) and 40-49 years (885, 22.16%). The reported incidence rate varied across different cities, ranging from 3.38 per 100 000 to 14.42 per 100 000. The proportion of adult cases among total cases showed a monthly increasing trend from 1.02% in January to 16.43% in December (P<0.001). The main clinical symptoms included nocturnal cough exacerbation (1 765, 45.42%) and paroxysmal spasmodic cough (1 253, 32.24%). Cases aged≥60 years had higher rates of complications [13.48% (81) vs 8.28% (272), P<0.001] and hospitalizations [20.47% (123) vs 6.06% (199), P<0.001] compared to those aged<60 years.

Conclusions

The incidence of pertussis among adults in Zhejiang Province was significantly increasing in 2024, with the proportion of adult cases rising month by month. Women aged 30 to 49 were the high-risk group, and the elderly bore a relatively heavy disease burden. The clinical manifestations were mainly atypical symptoms such as exacerbated nocturnal coughing.