Public Health Perspective on SARS Diagnostics

1. Public Health Perspective on SARS Diagnostics Stephen M. Ostroff Deputy Director National Center for Infectious Diseases, CDC

2. Outline • International & Domestic Experience with SARS • Public health imperatives for SARS diagnostics

3. SARS Case Definitions (USA) • Clinical Criteria • Fever (>38 C) & respiratory illness • Radiologic findings (pneumonia, RDS) • Autopsy findings (pneumonia, RDS) • Epidemiologic Criteria • Travel history (10 days) to SARS-affected area • Close contact with known or suspected SARS patient • Laboratory Criteria • Antibody to SARS-coV (acute or >28 days) • SARS-coV RNA by RT-PCR & 2nd PCR assay • Virus isolation

4. SARS Case Definitions (USA) • Suspect • Clinical & epidemiology criteria • Probable • Clinical & epidemiology criteria plus radiologic or autopsy evidence of pneumonia/RDS • Confirmed • Positive serology, PCR (x2), culture

6. US SARS Situation • >17,000 individual reports received • 423 persons met case definition • 348 (80%) suspected cases • 75 (20%) probable cases

7. SARS Case Demographics Factor Suspect Cases Probable Cases Age group <18 22% 22% 18-64 72% 56% 65+ 6% 21% Male/female 53%/47% 53%/47% Race/ethnicity White 61% 48% Asian 36% 49% Hospitalized >1 day 24% 61%

8. 14 Probable (n=75) 12 Suspect (n=348) 10 8 Number of cases 6 4 2 0 2/4 3/4 4/1 2/18 3/18 4/15 4/29 5/13 5/27 6/10 6/24 Date of illness onset Number of Probable and Suspect SARS Cases by Date of Illness Onset, United States, 2003 N = 423* *Includes 5 suspect/probable cases with illness onset before 2/1/03; data reported through July 10, 2003.

9. U.S. Probable SARS Cases N = 75 2 3 10 2 CT 3MA 2MD 0NJ 1 1 1 2 1 3 4 24 2 1 1 1 1 1 1 1 1 4 HI 2 Data as of 6/18/03

10. U.S. Probable SARS CasesN = 75 • 73 (97%) reported travel to areas with documented or suspected community transmission of SARS within the 10 days before illness onset • 1 (1%) HCW caring for SARS patient • 1 (1%) household contact of SARS patient Data as of 6/18/03

11. SARS Lab Specimens* Received at CDC (as of 7/9/03) Specimen TypeNo.Specimen TypeNo. Autopsy tissue 105 Stool 344 BAL/tracheal asp. 31 Urine 224 NP Swab Serum acute 546 acute 1,535 convalescent 73 convalescent 530 unknown 225 unknown 1,420 Sputum 325 Other 80 Throat wash/swab 141 TOTAL 5,579 *Includes both domestic & international

12. Diagnostic Findings Test No. Tested No. (%) Pos. Coronavirus Serology 2,742 188 (7%) RT-PCR 1,235 44 (4%) HMPV RT-PCR 218 21 (10%)

13. SARS-CoV Antibody TestingInterpretable Results United States, 2003 Type of CaseCoV+ Probable 8/45 (18%) Suspect 0/138 (0%) Data through 6/20/03

14. SARS-CoV+ Cases United States, 2003N = 8 • 7 reported travel* • 4 reported travel to Hong Kong • 2 reported travel to Toronto • 1 reported travel to both Singapore and Taiwan • 1 spouse of lab-confirmed SARS patient who had traveled to Hong Kong *defined as travel to areas with documented or suspected community transmission of SARS within the 10 days before illness onset MMWR 2003;52:570. Data through 6/18/03

15. Why do we need availability of good SARS diagnostic tests for public health purposes?

16. Public Health Rationale • Appropriate clinical management • Current • Future (therapeutics and prophylaxis) • Disease surveillance

17. Respiratory Tract Infections in Travelers • >600 million persons travel annually • >25% develop respiratory symptoms during travel; 10% following travel • 10-20% develop acute respiratory infection • Returning travelers seeking health care • 7.8% present with ARI (#2 complaint) • Travel to east Asia associated with ARI (OR 1.26 [95% CI 1.01-1.57]) Leder, et al CID 2003:399-406

18. Public Health Rationale • Public health control measures: • Hospital in- and out-patient management

20. Institutional Quarantine

21. Public Health Rationale • Public health control measures: • Community-based isolation & quarantine

22. Community Controls Cordon Sanitaire

23. 4:30pm July 11, 2003 Initial test results negative DYESS AIR FORCE BASE, ABILENE, Texas – The initial test results from the laboratory samples taken from eight Dyess Air Force Base members that may have been exposed to Sudden Acute Respiratory Syndrome are negative for the virus, according to health professionals with the 7th Medical Group at Dyess Air Force Base.Of the first samples that were sent to an Air Force lab and the Center for Disease Control and Prevention (CDC) for testing, two were positive for a common infectious bacteria known as Streptococcus pneumoniae, often seen in patients with pneumonia.Although the early samples are negative for SARS coronavirus, more testing is being conducted to rule out infection. Definitive results may not be in for another two to three weeks.So far, 10 people associated with Dyess Air Force Base have now been identified and isolated in their homes for possible SARS infection.All are currently stable or improving as of this morning. They remain isolated in their homes and have been instructed to stay there until released. CDC guidelines recommend release 10 days past the date of fever and respiratory symptoms.

24. Public Health Rationale • Public health control measures: • Contact tracing and testing • Epidemiologic investigations • Environmental/product sampling • Evaluation of viral shedding • Blood supply • Screening

25. Additional issues • SARS co-factors (HMPV, chlamydia) • Need to know it is SARS • Need to know it is something else • Ideal would be a multiplexed assay