Monday, June 22, 2015

BMC ID: Epidemiological Investigation Of Doctor Killed By H7N9 In Shanghai

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# 10,247

 

In January of 2014, during the 2nd winter wave of H7N9 in China, we saw headlines indicating an ER doctor in Shanghai died unexpectedly from the avian virus.  I described what we knew at the time in my blog of January 20th, - Shanghai, Zhejiang Report New H7N9 Cases (2 Fatal) - part of which read:

 

In the most high profile case – that of an ER doctor who worked at Pudong New Area People's Hospital – media reports suggest his early symptoms were atypical for influenza, consisting primarily of fever for the week before his death (see Atypical Influenza (H5N1,H7N9, pH1N1) Presentations).

According to a Shanghai Daily report overnight (see Doctor suspected to have died from H7N9), the doctor worked his shifts up until Friday despite his ongoing fever, but his condition suddenly deteriorated on Friday and he died Saturday morning of pneumonia and respiratory failure.  How, and where, he acquired the infection is unknown.


All too often we never hear any more about these cases, but in this case we have a detailed epidemiological investigation – published today in BMC Infectious Diseases – that provides additional details on this case.

 

Among other things, we learn that two other doctors who worked with this fatal case developed H7N9 antibodies, although neither fell ill.


First the Abstract from a much longer (open access) report, after which I’ll be back with more:

 

A case report of avian influenza H7N9 killing a young doctor in Shanghai, China

Hao Pan1, Xi Zhang1, Jiayu Hu1, Jian Chen1, Qichao Pan1, Zheng Teng1, Yaxu Zheng1, Shenghua Mao1, Hong Zhang2, Chwan-Chuen King3* and Fan Wu1*

BMC Infectious Diseases 2015, 15:237  doi:10.1186/s12879-015-0970-4

Published:
23 June 2015

© 2015 Pan et al.

Abstract

Background

The novel avian influenza H7N9 virus has caused severe diseases in humans in eastern China since the spring of 2013. On January 18 th 2014, a doctor working in the emergency department of a hospital in Shanghai died of H7N9 virus infection. To understand possible reasons to explain this world’s first fatal H7N9 case of a health care worker (HCW), we summarize the clinical presentation, epidemiological investigations, laboratory results, and prevention and control policies and make important recommendations to hospital-related workers.

Case presentation

The patient was a 31-year-old male Chinese surgeon who was obese and had a five-year history of hypertension and suspected diabetes. On January 11 th 2014, he showed symptoms of an influenza-like illness. Four days later, his illness rapidly progressed with bilateral pulmonary infiltration, hypoxia and lymphopenia. On January 17th, the case had a high fever, productive cough, chest tightness and shortness of breath, so that he was administered with oseltamivir, glucocorticoid, immunoglobulin, and broad-spectrum antibiotic therapy. The case died in the early morning of next day after invasive ventilation.

He had no contact with poultry nor had he visited live-poultry markets (LPMs), where positive rates of H7N9 were 14.6 % and 18.5 %. Before his illness, he cared for three febrile patients and had indirect contact with one severe pneumonia patient. Follow-up with 35 close contacts identified two HCWs who had worked also in emergency department but had not worn masks were anti-H7N9-positive. Viral sequence identity percentages between the patient and two LPM-H7N9 isolates were fewer than between the patient and another human case in shanghai in January of 2014.

Conclusions

Important reasons for the patient’s death might include late treatment with oseltamivir, and the infected H7N9 virus carrying both mammalian-adapted signature (HA-Q226L) and aerosol transmissibility (PB2-D701N). The LPM he passed every day was an unlikely source of his infection, but a contaminated environment, or an unidentified mild/asymptomatic H7N9 carrier were more probable. We advocate rigorous standard operating procedures for infection control practices in hospital settings and evaluations thereafter.

 

Although the official numbers remain small (roughly 650 H7N9 infections reported by China), the assumption is that these patients only represent the tip of the pyramid – the `sickest of the sick’ – who are most likely to seek medical care and therefore be identified as H7N9 cases.


Like most viruses, H7N9 can produce a wide spectrum of illness – ranging from asymptomatic (like the two seroconverted doctors above), to severe and even fatal illness. 

 

We’ve seen attempts to estimate the total number of infections in China – with some of those estimates ranging into the tens of thousands of cases (see Lancet: Clinical Severity Of Human H7N9 Infection).   While one can quibble over the size of this `uncounted’ cohort, few would argue their existence.


 
The mantra – repeated by Chinese officials for more than 2 years – has been that nearly all H7N9 infections are the result of direct contact with infected poultry. Human to human transmission only rarely occurs.

 

This study, however, suggests that this doctor (case X) may have acquired the virus from a human source and appears to have passed it on to two of his colleagues (cases Y & Z) – both of whom remained asymptomatic.


The entire report is well worth reading. In their closing remarks, the authors offer the following advice:

 

To minimize the health threat to citizens [17], the Shanghai Government announced the closure of LPMs from January 31 st to April 30 th 2014. There have been no H7N9 cases in Shanghai since February. Based on our experience, we recommend: (1) during epidemics of H7N9, those HCWs who might be exposed to H7N9 cases are advised to take oseltamivir or other available drugs against H7N9 viruses in advance; (2) implementing rigorous standard operating procedures for infection control practices, including PPE, traffic control [17], and evaluations thereafter; (3) enhancing surveillance by reporting of any HCWs who develop ILI; (4) avoiding possible cross-transmission among HCWs, patients, and visitors, particularly the immunocompromised and/or those with other co-morbidities [18], [19]; and (5) during H7N9 epidemics, H7N9 tests need to be performed on all severe cases of respiratory infection, severe pneumonia cases in particular, even these cases have no obvious epidemiologic exposures.