Title: Profile of Novel Flu Patients Admitted In Two Government Hospitals in Bangalore

Background: During the spring of 2009, a pandemic of novel flu emerged in Mexico and spread globally. We describe the profile of the patients who were hospitalized with the flu in two large government set ups in Bangalore. After warnings of flu outbreak these two hospitals were identified initially for screening and treatment for novel flu.

Objective: To study the profile of the flu patients admitted in two government set ups in Bangalore.

Methodology: Information regarding common clinical features, underlying medical condition and treatment outcome of the patients admitted with novel flu in two government set ups in Bangalore till November 15^th was collected.

Observations: In the study 54.4% of the patients were in the age group of 16-35 years,61.6% were males ,36% of the patients presented after two days of symptoms, 83% presented with fever, 72.3% presented with cough and 33% with breathlessness. The study revealed that 17% of the patients had history of travel to novel flu affected areas ,6.2%  history of contact with novel flu cases and 6.2% both travel and contact. For majority of patients the duration of stay in the hospital was 4-6days (51.7%), 12 patients (10.7%) had history of underlying   comorbid conditions. In the study 19 patients (16.9%) were treated with steroids and 31(27.6%) were admitted in ICU (intensive care unit) and 26 patients died (23.2%) all in age group of 16-35 years.

Conclusion: In our study majority of the patients were 16-35 years old, presented to the hospital after two days with fever, cough and breathlessness as the predominant symptom and less than half of them had history of travel or contact. Most of the patients recovered and death was reported in 23.2% of the patients.

Key words: Novel flu, symptoms, profile, comorbid conditions

Introduction

Novel flu is a new influenza caused by quadruple reassortment virus, that is it has 2 genes from flu viruses circulating in pigs in Europe and Asia, bird genes and human genes.¹

The first case emerged in Mexico on April 15 2009, then it spread leading to a global pandemic and WHO raised the pandemic alert to phase 6 on June 11 2009.² In India a total of 15411 cases have been reported of which 523 died .In Karnataka a total of 1530 cases have been reported of which 118 died(as on 15^th November.)³

The information analyzed by CDC (Center for Disease control) supported the conclusion that novel H1N1 flu caused greater disease burden on people younger than 25 years than older people.⁴The symptoms are similar to seasonal flu although vomiting and diarrhea has been reported more commonly with H1N1.⁴ The number of deaths is also higher in 25-49 years of age.⁴

In India initially surveillance was started at airports and then extended to community level. In order to make the testing facility more accessible at large and due to onset of flu season in the country, it was decided to revise the guidelines. Thus persons presenting with flu like symptoms were categorized into category A (Patients with mild fever plus cough / sore throat with or without body ache, headache, diarrhea and vomiting) category B(in addition to signs and symptoms of category A if the patient has high grade fever and severe sore throat or having one or more of the following high risk conditions like children less than 5 years old, pregnant women persons aged 65 years or older, patients with lung diseases, heart disease, liver disease, kidney disease, blood disorders, diabetes, neurological disorders, cancer and HIV/AIDS and patients on long term cortisone therapy) and category C(In addition to the above signs and symptoms of Category-A and B, if the patient has breathlessness, chest pain, drowsiness, fall in blood pressure, irritability among small children, refusal to accept feed, worsening of underlying chronic conditions). ⁵ Testing is done only for category C and pharmacological treatment given for category B and C.⁵

In order to find out the age distribution common clinical features, underlying medical condition and treatment outcome in patients admitted in two government hospitals in Bangalore we decided to do a study of profile of the patients admitted with novel flu in these two hospitals from June till November 15^th . By studying the profile of the patients we will come to know the common age group, symptoms, underlying medical condition and treatment outcome thus helping us in better management of the future cases

Methodology

The study was conducted in the two largest government set ups of Karnataka. After few cases of novel flu were reported these two hospitals were identified initially for screening and treatment for novel flu, then later other centers were identified. After obtaining permission from the directors of these two institutions information regarding  common clinical features, underlying medical condition and treatment outcome of the patients admitted with novel flu in the two set ups from June till November 15^th(a total of 112 patients) was collected by record analysis. It is a hospital based study.

Results

The study revealed that out of 112 patients 32.1% of the admitted patients were in the age group of 26-35 years,17% less than 15 years and 3.6% of the patients were in the age group of 56-65 years.61.6% were males and 38.4% were female (refer table 1).

The study revealed that 38.6% of the patients presented after two days of symptoms and 27.7% after more than six days (refer table 2 ). 83% presented with fever,72.3% presented with cough, 33.03% with breathlessness and 18.75% with sore throat (refer table 3).

The study revealed that 17% of the patients had history of travel to novel flu affected areas, 6.3% history of contact with novel flu cases and 6.3% had history of both travel and contact. While in the patients admitted before mid September 31.7% of the patients had history of travel to novel flu affected areas,11.7% had history of contact with novel flu cases,11.7% had both travel and contact history. Thus demonstrating the presence of disease in the community (History of contact-patients had been in contact with a case of novel flu in the past seven days ,history of travel to areas where there are one or more confirmed novel flu cases, in the past seven days.⁶)(refer table 4)

The study   revealed that for majority of patients (51.7%) the duration of stay in the hospital was 4-6 days (refer table 5).

12 patients (10.7%) had history of underlying comorbid conditions like diabetes mellitus, coronary heart disease, hypertension, Chronic obstructive pulmonary disease (COPD), HIV etc (refer table 6).Two patients were known smoker and three were smoker and alcoholic.17 patients (15.2%) had been treated earlier in other hospitals for the same complaints. 43.3% of the patients had pharyngeal congestion,13.3% had abnormal chest finding and 0.05% had cyanosis. All the patients were treated with oseltamivir, antibiotics and symptomatic management, 19 patients (16.9%) were treated with steroids and 31(27.6%) were admitted in ICU(intensive care unit).

Of the 112 patients admitted 26 patients died (23.2%) most of them were in age group of 16-35 years (refer table 7&8).All the patients developed Acute Respiratory Distress Syndrome (ARDS) followed by Multi organ Dysfunction Syndrome (MODS) and succumbed to death. The remaining fifty six patients who recovered were admitted for a mean duration of five days and treated with oseltamivir, antibiotics and symptomatic management.

Discussion

The study revealed that most of the patients was in the age group of 16-35 years and the median age was 27 years. While in a study done in California hospitalization rates were highest for young adults ages 18 to 29 and lower for older people and the median age was 27 years.⁷ The study revealed that 17% of the patients were less than 15 years while a study in Mexico showed 41.9% of patients were aged less than 15 years.⁸ This is in contrast to peak periods of seasonal influenza, when influenza hospitalizations are more common among persons 65 years of age or older and those under the age of 5 years.⁹ The study revealed almost half the hospitalizations involved persons under the age of 35 years and only 0.9% were more than 55 years of age. Possible explanations for this phenomenon include the fact that children are more likely to be exposed in schools, the young have a greater susceptibility to the virus (as compared with persons >60 years of age) and young febrile patients are more likely to be tested, since older adults with influenza often do not have fever.¹⁰ In the study 10.7% had history of underlying comorbid conditions while a study in California showed 64% had underlying medical conditions.¹¹The most common symptoms in the study patients were fever, cough, and breathlessness this is similar to the findings of a study done in California.¹¹The study revealed that 19 patients(16.9%) were treated with steroids, similar study done in United States showed 36% received such drugs.¹⁰The study revealed that 31 patients (27.6 %) admitted in ICU(intensive care unit) and were in age group of 16-35 years, this is similar to findings of a study done in United States which revealed that 25% of the patients were admitted to an ICU and the median age of those who were admitted to an ICU was 29 years.¹⁰

In this study out of 112 admitted patients 26 (23.2%) died while in a study done in California of the 1088 hospitalization, 118 were deaths, which translates into a fatality rate of 11 per cent. ⁷ The higher number of deaths reported in the study may due to the change in criteria for admission which recommended admission for only seriously ill patients. The study revealed that for patients older than 50 years the mortality rate was 19.1% which is similar to a study in California which showed that for people age 50 and older, the fatality rate was as high as 20 per cent.⁷ This study revealed that the most common cause of death was acute respiratory distress syndrome which is similar to a study done in California where the most common causes of death were viral pneumonia and acute respiratory distress syndrome, which are complications of influenza. ⁷ Most of the patients who died were in the age group of 16 -35 which is similar to the previous study which showed persons age 20–40 accounted for the bulk of the excess deaths.¹²

Conclusion: The study that demonstrated that novel flu (H1N1) infection-related critical illness predominantly affects young patients with few major comorbid conditions and is associated with severe hypoxemic respiratory failure, often requiring prolonged mechanical ventilation. Although serologic studies suggest that influenza A (H1N1) is a novel influenza strain with little protection afforded by seasonal influenza vaccination, adults older than 60 years appear to have some preexisting immunity to this novel virus. Fever and respiratory symptoms were harbingers of disease in almost all cases. Most of the patients who died were more likely to have higher severity of illness at presentation and greater organ dysfunction

Conflict of interest :none

References

1.2009 H1N1 Flu (“Swine Flu”) and You. Available fromURL:http://www.cdc.gov/h1n1flu/qa.htm .[cited  on 2009 October 11^th ]

2. Novel H1N1 Flu: Background on the Situation. Available fromURL:http://www.cdc.gov/h1n1flu/background.htm .[cited  on 2009 October 11^th ]

3.Consolidated Status of Influenza A H1N1. Available from URL: http://mohfw-h1n1.nic.in/. [cited on 2009 November 15^th ]

4.Novel H1N1 Flu: Facts and Figures. Available From URL: http://www.cdc.gov/H1N1flu/surveillance.qa.htm. [cited on 2009 October 4^th ]

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screening for home isolation, testing treatment, and hospitalization. Available from URL: http://mohfw-h1n1.nic.in/ . [cited on 2009 November 6^th ]

6.Human swine influenza a pandemic alert.CD Alert March-April 2009;12(8).Available From URL: http://www.mohfw.nic.in/Upld_CDA_Swine.pdf. [cited  on 2009 October 13^th ].

7.JK Louie, M Acosta, K Winter, et al. Factors associated with death or hospitalization due to pandemic 2009 influenza A (H1N1) infection in California. JAMA 2009; 30(17): 1896-902.Available from URL: http://jama.ama-assn.org/cgi/content/abstract/302/17/1896. [cited on 2009 Dec 4^th]

8.Update: Novel Influenza A (H1N1) Virus Infection -Mexico, March–May, 2009 June 5, 2009; 58(21);585-589.

9.Thompson WW, Shay DK, Weintraub E, et al. Influenza-associated hospitalizations in the United States. JAMA 2004;292:1333-1340.

10.Jain et al. Hospitalized Patients with 2009 H1N1 Influenza in the United States, April–June 2009. N Engl J Med 2009;361. Available From URL :http://www.nejm.org .[cited on 2009 October 12^th ].

11.Hospitalized Patients with Novel Influenza A (H1N1) Virus Infection -California, April–May, 2009.On May 18, this report was posted as an MMWR Early Release on the MMWR web.  Available From URL:http://www.cdc.gov/mmwr.[cited on 2009 October 19^th ].

12.Jeffrey Luk,Peter Gross,¹William W. Thompson Observations on Mortality during the 1918 Influenza Pandemic Clinical Infectious Diseases 2001;33:1375–1378

Table no 1: Age group and sex of the patients

Our study showed most of the patients was in the age group of 16-35 years. While in a study done in California hospitalization rates were highest for young adults ages 18 to 29.But the median ages were similar in both the studies that is 27 years

Table no 2: Duration of complaints before reporting to the hospital

Most of the patients reported after two days of symptoms.

Table no 3: Presenting symptoms

The presenting symptoms were fever, cough, running nose and sore throat,this is similar to the findings of a study done in California

Table no 4: Contact and travel history

History of contact-patients had been in contact with a case of novel flu in the past seven days.

History of travel-patients had traveled to novel flu affected countries in the past seven days.

 Table no 5: Duration of stay in the hospital

In our study most of the patients were admitted for duration of 4-6 days.

 Table no 6: Presence of other comorbid conditions

Majority of the patients were apparently healthy others had comorbid conditions like diabetes mellitus, coronary heart disease, hypertension and HIV, while a study in California showed 64%  had underlying medical conditions.

Table no 7: Outcome of admitted patients

26 patients died and remaining recovered, who recovered were admitted for a mean duration of five days and treated with oseltamivir, antibiotics and symptomatic management.

Table no 8: Outcome in various age groups

Proportion of deaths was higher in the age group of 55-65 years. Most of  the patients who died were in the age group of 16 -35 which is similar to the previous study which showed persons age 20–40 accounted for the bulk of the excess deaths.¹²