Measles is caused by measles virus belonging to genus
Measles is a highly infectious respiratory disease that occurs worldwide, which mainly causes morbidity and mortality among children. Its causative agent, the measles virus, is a single stranded negative sense RNA virus belonging to the Paramyxoviridae family [
On March 16, 2015, a patient admitted to the Emergency Department with high fever was diagnosed as having a measles infection. On the day of March 20, 2016, three nurses from Emergency Department who had direct and (or) indirect contact with the patient displayed similar clinical signs including fever and rash that were determined to be positive for measles infection. The hospital noticed that it might be a break of measles infection with possibility of nosocomial transmission, and the first case on March 16, 2015, was suspected to be the source of this outbreak. Immediately, a series of measures for the prevention and control of nosocomial measles according to Guidelines of the People’s Republic of China on the Prevention and Control of Infectious Diseases have been set up as follows.
Setting up isolation wards in a well-ventilated old building. Enhancing ventilation, isolation, and disinfection measures in isolation areas. Isolating those patients with great transmission potentials including severe-ill patients and students. Providing measles immunization to a total of 2,400 hospital staff. Close monitoring of the measles infected patients, paying much more attention to patients with severe complications, and canceling multidisciplinary team meetings and treatment.
First, the isolation ward was set up with a well-ventilated system to prevent possible transmission among community people and the first patient (case number 1) was hospitalized two weeks before discharge. Second, Emergency Department is the unit with serious and multiple illness in which the healthcare staff from other departments who went to consultation directly or indirectly were exposed to the Emergency Department patients with measles; they were infected with measles and/or spread it to other staff in their departments. Therefore, more medical staffs from other departments with similar symptoms and close contact with the known measles cases were searched. Third, reimmunization probably played important roles in containing measles transmission and a total of 2400 hospital staff were given a measles immunization before March 27, 2015. Since then, new measles case numbers began to decrease and the last two cases were reported on April 4, 2016 (Figure
An epidemic curve shows the number of cases during the measles outbreak in Lanzhou University Second Hospital between March 16, 2016, and April 4, 2015. The
Patients with clinical symptoms including fever, rash, and/or conjunctivitis were defined as suspected measles cases. Between March 16 and April 4, 2015, both serum and throat swab samples were gathered from 102 suspected measles cases and then tested for measles virus IgM using IgM ELISA test kit (Zhuhai SEZ Haitai Biological Pharmaceuticals Co., Ltd., Zhuhai, China) and for measles virus RNA using a real-time reverse transcription PCR kit (Jiangsu BioPerfectus Technologies Co., Ltd., Jiangsu, China). Finally, 60 suspected measles cases were confirmed as the diagnosis of measles infection among whom there were 51 (85.00%) cases positive for measles IgM, 50 (83.33%) for measles virus RNA, and 41 (68.33%) for both measles IgM and virus RNA. Among the 60 positive cases, 39 (65.00%) and 21 (35.00%) were in female and male patients, respectively. Seven cases (11.66%) were aged 1–18 years, 50 cases (83.33%) were aged 21–40 years, and 3 cases (5.01%) were aged >40 years (Table
Summary of cases diagnosed with measles in the outbreak.
|
|
Female ( |
39 (65.00%) |
Male ( |
21 (35.00%) |
|
|
1–18 years ( |
7 (11.66%) |
19–40 years ( |
50 (83.33%) |
>40 years ( |
3 (5.01%) |
|
|
New building of the hospital ( |
60 (100%) |
Old building of the hospital ( |
0 (0.00%) |
|
|
Nurse ( |
31 (51.66%) |
Staff ( |
11 (18.33%) |
Clinical patient ( |
10 (16.66%) |
Doctor ( |
7 (11.66%) |
Medic ( |
1 (1.69%) |
|
|
Vaccination ( |
44 (73.33%) |
Unknown ( |
12 (20.00%) |
No vaccination ( |
4 (6.67%) |
|
|
MV IgM ( |
51 (85.00%) |
MV PCR ( |
50 (83.33%) |
Both ( |
41 (68.33%) |
|
|
Koplik spots ( |
36 (60.00%) |
Catarrh ( |
51 (85.00%) |
Conjunctivitis ( |
50 (83.33%) |
Complication ( |
|
Pneumonia ( |
2 (3.33%) |
Laryngitis ( |
1 (1.67%) |
Liver dysfunction ( |
6 (10.00%) |
General information and clinical manifestations of measles patients.
Case number | Date of onset | Gender | Age (years) | Occupation | Vaccination history | MV IgM | MV PCR | Clinical manifestation | |||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Koplik spots | Catarrh | Conjunctivitis | Pneumonia | Laryngitis | Liver dysfunction | ||||||||
1 | Mar. 16 | Female | 33 | ED patient | No | Positive | Positive | Yes | Yes | Yes | Yes | No | Yes |
2 | Mar. 20 | Female | 29 | ED nurse | Yes | Positive | Positive | Yes | Yes | Yes | No | No | Yes |
3 | Mar. 20 | Female | 27 | ED nurse | No | Positive | Positive | Yes | Yes | Yes | No | No | Yes |
4 | Mar. 20 | Male | 31 | ED nurse | Yes | Positive | Positive | Yes | No | Yes | No | No | No |
5 | Mar. 23 | Male | 26 | Logistical staff | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
6 | Mar. 23 | Female | 25 | Surgical nurse | Yes | Positive | Positive | No | Yes | No | No | No | No |
7 | Mar. 23 | Male | 36 | Logistical staff | Unknown | Positive | Positive | No | Yes | Yes | No | No | No |
8 | Mar. 23 | Female | 31 | Surgical nurse | Unknown | Positive | Positive | Yes | No | Yes | No | No | No |
9 | Mar. 23 | Female | 41 | Logistical staff | No | Positive | Positive | No | Yes | Yes | No | No | No |
10 | Mar. 23 | Male | 32 | Neurological doctor | Unknown | Positive | Positive | No | Yes | Yes | No | No | No |
11 | Mar. 23 | Female | 26 | Hematological nurse | Yes | Positive | Positive | Yes | Yes | No | No | No | No |
12 | Mar. 23 | Male | 32 | Logistical staff | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
13 | Mar. 23 | Male | 27 | Logistical staff | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
14 | Mar. 23 | Male | 25 | Pediatric nurse | Yes | Positive | Positive | No | No | No | No | No | No |
15 | Mar. 23 | Male | 29 | Logistical staff | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
16 | Mar. 23 | Female | 27 | Respiratory nurse | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
17 | Mar. 23 | Female | 24 | Ophthalmological nurse | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
18 | Mar. 24 | Male | 27 | Logistical staff | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
19 | Mar. 24 | Male | 24 | Cardiology nurse | Yes | Positive | Negative | Yes | Yes | Yes | No | No | No |
20 | Mar. 24 | Female | 23 | Clinic nurse | Yes | Positive | Negative | Yes | Yes | Yes | No | No | No |
21 | Mar. 24 | Female | 24 | Clinic nurse | Yes | Positive | Negative | Yes | Yes | Yes | No | No | No |
22 | Mar. 24 | Female | 25 | Clinic nurse | Yes | Positive | Negative | Yes | No | Yes | No | No | No |
23 | Mar. 24 | Male | 30 | Neurological doctor | Yes | Positive | Negative | No | Yes | Yes | No | No | No |
24 | Mar. 24 | Female | 22 | Surgical nurse | Yes | Positive | Negative | No | Yes | No | No | No | No |
25 | Mar. 24 | Female | 25 | Surgical nurse | Yes | Positive | Negative | Yes | Yes | Yes | No | No | No |
26 | Mar. 24 | Female | 24 | Neurological nurse | Yes | Positive | Negative | Yes | Yes | Yes | No | No | No |
27 | Mar. 24 | Female | 25 | Surgical nurse | Yes | Positive | Negative | No | Yes | Yes | No | No | No |
28 | Mar. 24 | Male | 1 | Hematological patient | Yes | Positive | Positive | Yes | Yes | Yes | Yes | Yes | Yes |
29 | Mar. 25 | Female | 27 | Obstetrical patient | Yes | Positive | Positive | Yes | Yes | Yes | No | No | Yes |
30 | Mar. 25 | Female | 30 | ICU nurse | Unknown | Positive | Positive | No | No | No | No | No | No |
31 | Mar. 25 | Female | 26 | Neurosurgical nurse | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
32 | Mar. 25 | Female | 28 | Urological nurse | Unknown | Positive | Positive | Yes | Yes | Yes | No | No | No |
33 | Mar. 25 | Female | 19 | VIP medical nurse | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
34 | Mar. 25 | Female | 32 | Cardiology nurse | Unknown | Positive | Positive | No | Yes | No | No | No | No |
35 | Mar. 26 | Female | 13 | Pediatric patient | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
36 | Mar. 26 | Male | 30 | Chinese medicine doctor | Unknown | Positive | Positive | Yes | Yes | Yes | No | No | Yes |
37 | Mar. 26 | Female | 27 | VIP medical nurse | Yes | Positive | Positive | Yes | No | Yes | No | No | No |
38 | Mar. 26 | Female | 26 | Cardiology nurse | Yes | Positive | Negative | Yes | Yes | Yes | No | No | No |
39 | Mar. 27 | Male | 16 | ED patient | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
40 | Mar. 27 | Male | 30 | Urological doctor | Unknown | Positive | Positive | No | Yes | No | No | No | No |
41 | Mar. 27 | Female | 29 | Logistical staff | Yes | Negative | Positive | Yes | Yes | Yes | No | No | No |
42 | Mar. 27 | Male | 21 | Medical student | Yes | Negative | Positive | No | Yes | Yes | No | No | No |
43 | Mar. 27 | Male | 14 | ED patient | Yes | Positive | Positive | Yes | Yes | No | No | No | No |
44 | Mar. 27 | Male | 25 | Logistical staff | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
45 | Mar. 27 | Female | 27 | Cardiology nurse | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
46 | Mar. 27 | Female | 38 | ED patient | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
47 | Mar. 27 | Male | 1 | Pediatric patient | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
48 | Mar. 28 | Female | 27 | Clinic nurse | Yes | Positive | Positive | No | Yes | Yes | No | No | No |
49 | Mar. 28 | Female | 16 | ED patient | Yes | Positive | Positive | Yes | No | No | No | No | No |
50 | Mar. 28 | Female | 22 | Neurological nurse | Yes | Positive | Positive | Yes | Yes | Yes | No | No | No |
51 | Mar. 28 | Male | 13 | Pediatric patient | Yes | Positive | Positive | Yes | Yes | No | No | No | No |
52 | Mar. 28 | Female | 29 | Hematological nurse | Unknown | Positive | Positive | No | Yes | Yes | No | No | No |
53 | Mar. 29 | Female | 43 | Logistical staff | No | Positive | Positive | No | Yes | Yes | No | No | No |
54 | Mar. 29 | Female | 27 | Pediatric nurse | Yes | Negative | Positive | Yes | Yes | Yes | No | No | No |
55 | Mar. 30 | Female | 38 | Nephrology doctor | Unknown | Negative | Positive | Yes | Yes | Yes | No | No | No |
56 | Mar. 31 | Female | 25 | Urological nurse | Yes | Negative | Positive | No | No | Yes | No | No | No |
57 | Apr. 2 | Female | 47 | Logistical staff | Unknown | Negative | Positive | Yes | Yes | Yes | No | No | No |
58 | Apr. 2 | Female | 29 | Pediatric nurse | Yes | Negative | Positive | No | Yes | Yes | No | No | No |
59 | Apr. 4 | Male | 32 | Logistical staff | Unknown | Negative | Positive | Yes | Yes | No | No | No | No |
60 | Apr. 4 | Female | 23 | Neurological nurse | Yes | Negative | Positive | No | No | Yes | No | No | No |
ED: Emergency Department; ICU: intensive care unit; VIP: very important person.
The results of a recent study of measles infections in China indicated that measles usually occurred in young unvaccinated children [
In summary, our study reports a measles outbreak that occurred among adult healthcare workers who were previously underimmunized against measles. It highlights that healthcare workers need to be fully vaccinated through a 2-dose measles vaccine program, which could greatly prevent nosocomial outbreak of measles. Equally important, fever clinics should be separated from other divisions in the hospital. Vigilant attention should be paid to the patients with the clinical fever and rash symptoms and early isolation and definite diagnosis of the measles suspected medical staff patients to avoid a possible nosocomial transmission of measles infection.
Dr. Zhang is the director of the Department of General Medicine, Lanzhou University Second Hospital, Gansu, China. His research interest is cardiovascular disease.
The authors declare that there are no competing interests regarding the publication of this paper.
All authors read and approved the final paper. Zhengyi Zhang, Yuan Zhao, and Jing Yu conceived and designed the experiments. Zhengyi Zhang, Yuan Zhao, Lili Yang, Changhong Lu, Ying Meng, Xiaoli Guan, and Hongjin An performed the experiments. Zhengyi Zhang, Yuan Zhao, Meizhong Zhang, Wenqin Guo, and Jing Yu analyzed the data. Zhengyi Zhang, Yuan Zhao, and Jing Yu wrote the paper. Zhengyi Zhang and Yuan Zhao contributed equally to this work.
The authors would like to thank staff in Department of Public Health and Department of Medical Affairs for providing data on measles outbreak. Thanks extended to Lanzhou Center for Disease Control and Prevention for technical help on the measles diagnostic assays.