Swine Flu ( Infl uenza A H 1 N 1 2009 ) infection in pregnancy-a profi le of cases at a large tertiary centre in Dubai

Al Wasl maternity and paediatric hospital is a large tertiary referral centre in UAE for northern emirates with a delivery rate of 7000/year. It has a 24-hour walk-in clinic attached to Obs/Gyn emergency that serves patients presenting via self-referral, peripheral health centres and private hospitals. Our study included a cohort of pregnant and postpartum women presenting between 3 rd august and 17 th December 2009 with fever and acute respiratory illness and confi rmed positive for H1N1 infl uenza A (2009) by nasopharyngeal swab polymerase chain reaction (PCR). A special laboratory was set up to provide results in 24–48 hours. Emergency and obstetric case records of these women were reviewed to extract demographic and clinical data and entered into a data collection tool in Excel format. Data were analysed and descriptive statistics were used.


INTRODUCTION
The H1N1 infl uenza A (2009) pandemic affected most countries of the world and 3287 confi rmed cases have been reported from Dubai emirate with 7 deaths (Dubai Health Authority information-Personal communication).UAE has large number of visitors and expatriate population that includes pregnant women.According to observations from past seasonal infl uenza epidemics, pregnant women are at increased risk of severe disease and infl uenza related hospital admissions 1 .Since the outbreak, our centre has managed a large number of pregnant women with H1N1 infl uenza A (2009) infection in the region.Our aim was to study the characteristics of women presenting with H1N1 infl uenza A (2009), their immediate outcome and complications.
Contacts of confi rmed cases were traced and treated in peripheral health centres.WHO guidelines were used in management of cases with special attention to hand hygiene and use of PPE (personal protective equipment) when attending these cases.Cases were admitted according to their clinical condition, (indications being high fever > 38°C, severe respiratory symptoms +/-co morbidity) in isolation rooms in different wards of the hospital.Clinically stable patients were discharged on oseltamivir and advised to self-isolate at home.They were contacted on phone to discontinue oseltamivir, if PCR result came negative and were advised to return to hospital if there was deterioration in symptoms even after 48 hours of treatment.

RESULTS
226 pregnant and postpartum women suspected to have swine fl u infection were seen in the obstetrics & Gynaecology unit of Al Wasl hospital between 3 rd august to 17 th December 2009 of which 96 cases (42.4%) were confi rmed positive.The characteristics of these women are shown in table 1 .The mean age was 31 years, (range: 18 -44 yrs.) 51% were local Arabs, 12.5% other Arabs and 36.5% were non Arabs.Two-fi fths of women (40%) were nulliparous and rest were multiparous.The mean gestational age at presentation was 22 weeks (range: 6 -39 weeks).5 cases of 96 (5.2%) were post delivery.10% cases gave history of travel and also 10% gave history of close contact with a positive case of swine fl u. 14 cases in our cohort (14.5%) had co morbidity such as Diabetes mellitus (8 cases), Hypertension (1 case), Gestational diabetes + Hypertension (2 cases), malaria (1 case) and urinary tract infection (2 cases).93.7% women presented with high temperature,headache and one or more symptoms of upper respiratory tract infection(cough, rhinorrhoea, sorethroart).Majority (93.7%) of cases presented within 2 days of symptom onset .49% cases were admitted and 51% were treated as outpatients.92.7% received oseltamivir treatment.7 cases declined oseltamivir but accepted other treatments for common cold.The interval between symptom onset and start of treatment ranged from 2-3 days.The duration of hospitalisation was 3-5 days (mean: 4 days).Pregnancy complications were seen in 5.2% cases (Hyper emesis, oligamnios and ante partum haemorrhage).6 of 7 cases who had refused oseltamivir recovered and 88 cases who received oseltamivir recovered completely but one woman of Indian origin aged 34 yrs., who presented on 9 th post caesarean day with severe illness, needed ICU admission and intubation due to respiratory failure.She had Insulin dependent Diabetes mellitus and hypertension.In spite of the best supportive measures she developed multiorgan failure and died subsequently.
During the study period all 2 nd and 3 rd trimester cases were followed up till delivery and none had foetal abnormalities. 1 st trimester cases (32 of total 91) were followed according to registry maintained for swine fl u cases in our centre.27 of them delivered at our hospital and none had foetal abnormalities.

DISCUSSION
As soon as news was received from other countries about swine fl u cases, the infection control committee of our hospital and the central infection control committee for DHA (Dubai health authority) took active measures to contain the spread of H1N1 A infl uenza virus.Keeping in mind the lessons from epidemiological evidence that pregnant women, due to immune-suppression are more prone for complications if they develop infl uenza and starting anti-viral therapy within 48 hours of symptoms can aid recovery 2 , there were widespread media campaigns to educate public and lectures to educate physicians about the nature and effects of swine fl u.
Antiviral drugs are not a cure but reduce the duration of illness, secondary complications and mortality. 2ommonly used drugs are the neuraminidase inhibitors, oseltamivir (oral) and zanamivir (given by inhalation).
In comparison to oseltamivir, zanamivir is effective in respiratory tract but does not reach effective levels systemically .Presently Oseltamivir resistance is rare and no onward transmission of resistant virus has occurred 3 .In spite of explanation of safety, 7 of our cases had declined oseltamivir (1 case was on antimalarial and had excessive vomiting, 2 cases were in fi rst trimester and anxious about fetal anomalies and 4 cases were concerned about drug adverse effects).WHO guidelines were strictly followed for management of cases.Posters were put in all strategic locations in the hospital and information booklets made available to all women attending hospital.Treatment was given free of cost to all suspected cases.Due to these factors and increased public awareness, panic was minimised and majority of cases (93.7%) presented early, within 2 days of symptom onset and treatment was started early leading to complete recovery in all except one case which presented late with severe illness and ended in mortality.
In the study published by ML Lim et al in February 2010 4 , there were 11 cases of morbidity and no mortality.In a series published by Jamieson and co-workers comprising 34 women from 13 states in USA, there were 10 morbidity and 1 mortality case 4 .
It is interesting to note that 63% cases in our cohort were from Arab population ( Table 1 ).This may be attributable to cultural factors like large family gatherings and greeting by kissing.5 of 96 cases (5.2%) in our cohort developed swine fl u infection postpartum.4 of them showed symptoms on 2 nd postnatal day while in hospital, were discharged on recovery after 2 days of oseltamivir treatment.Oseltamivir was continued during breastfeeding as the drug and its metabolite are excreted in breast milk in very small quantity and unlikely to have clinical sequelae in the infant.Women were reassured about the safety of the drug 2 .The 5 th case, who was hypertensive and diabetic on treatment, was discharged on 4 th post caesarean day in good general condition, but acquired the infection in community and presented on 9 th postnatal day to our emergency with respiratory distress.She was intubated and admitted to ICU and died after 5 days.Breathlessness, a symptom of respiratory complication is a strong predictor for both ICU requirement and death 3 .Mortality in our case confi rms the signifi cance of this feature as also the report by Jain and colleagues, in which dyspnoea was more likely to be seen in H1N1 A infl uenza patients admitted to ICU and in those who died 5 .

CONCLUSION
The effect of swine fl u infection on our cohort was mild due to early diagnosis and initiation of antiviral therapy.Oseltamivir was well tolerated by majority .Co-morbidity and delay in seeking medical help lead to severe illness and mortality.We recommend vaccination with Pandemrix (single dose vaccine with excellent safety profi le 1 .)for all pregnant women and their direct health carers if there is a future outbreak of this infection.