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a 36-year - old , previously healthy , asian woman ( gravida 2 , para 1 ) at 19 weeks gestation with a low - lying placenta traveled in late february from the united states to hong kong with her husband and child . before departing from the united states ,
the patient had been complaining of a mild , intermittent cough without fever for approximately 10 days .
the cough , similar to one she had during her previous pregnancy , did not impair her ability to function . while in hong kong , between february 19 and march 2 , 2003 , she stayed at the same hotel and on the same floor as a physician from southern china , who is believed to have been the source of infection for patients who were the index case - patients in subsequent outbreaks of sars in hong kong , singapore , hanoi , and toronto , canada ( 11 ) . on february 24 , fever , headache , weakness , anorexia , increasing cough , and shortness of breath developed in the patient . the next morning , she sought medical attention and was prescribed chlorpheniramine and acetaminophen .
her symptoms worsened , prompting her to see another physician 2 days later . a fetal ultrasound performed at this time was reportedly normal .
cephalexin was added to her regimen , but her condition did not improve ; that night , she noted blood - tinged sputum . on march 2 , the patient returned to the united states where , acutely short of breath , she was hospitalized with pneumonia .
although chest auscultation was normal , chest radiography showed diffuse bilateral lower lobe infiltrates ( figure , part a ) .
admission arterial blood gas analysis showed ph 7.47 , paco2 31 mm hg , and pao2 75 mm hg on room air .
other pertinent laboratory findings included a leukocyte count of 3,300/mm ( normal range 4,50011,500/mm ) with a differential of 83% polymorphonuclear cells , 12% lymphocytes , and 5% monocytes ; platelets of 103,000/mm ( normal range 150,000450,000/mm ) ; and alanine aminotransferase of 42 u / l ( normal range 1040 u / l ) .
she was given supplemental oxygen for hypoxia and intravenous azithromycin and ampicillin to treat typical and atypical respiratory pathogens associated with community - acquired pneumonia .
a fetal ultrasound performed on march 3 demonstrated a live intrauterine fetus of approximately 21 weeks gestational age and complete placenta previa . despite antibiotic therapy , over the next 3 days ,
the patient became increasingly dyspneic ; rales and decreased breath sounds developed , and she had radiographic evidence of progressive pulmonary infiltrates ( figure , part b ) . during this time , ticarcillin - clavulanate was added to her antimicrobial regimen , and rifampin was initiated as adjuvant therapy for possible legionellosis . because the patient s diagnosis remained elusive ,
tuberculosis was considered , and she was placed in airborne isolation . arterial blood gas analysis on march 5 showed : ph 7.48 , paco2 31 mm hg , and pao2 57 mm hg on a 100% nonrebreather mask .
the patient was subsequently placed on a mechanical ventilator . when avian ( h5n1 ) influenza was considered in the differential diagnosis
chest auscultation demonstrated few bibasilar rales , and a chest radiograph showed interval improvement ( figure , part c ) .
, she had a fetal ultrasound that showed fetal growth consistent with dates and complete placenta previa . on march 17
sputum , blood , and urine cultures ; smears for acid - fast bacilli ; and tests for legionella urinary antigen , influenza nasopharyngeal antigen , and cold agglutinins were negative .
serum specimens collected 12 and 29 days after illness onset were tested at the centers for disease control and prevention ( cdc ) and found to be positive for sars - cov antibody .
chest radiographs of case - patient with severe acute respiratory syndrome ( sars ) while pregnant .
a , day 6 of illness ; b , day 10 ; c , day 13 .
a follow - up ultrasound examination on april 29 during routine prenatal care showed fetal growth consistent with dates and persistent complete previa . on may 2 ( approximately 30 weeks gestation ) , the patient was diagnosed with gestational diabetes after an abnormal oral glucose tolerance test .
because serial ultrasounds performed on may 28 and june 24 demonstrated complete placenta previa , she underwent a cesarean section at 38 weeks gestation .
after informed consent was obtained , the following specimens ( collected approximately 130 days after illness onset ) were submitted to cdc for coronavirus testing : serum , whole blood , nasopharyngeal and rectal swab specimens from the mother , postdelivery placenta , cord blood , amniotic fluid , and breast milk .
antibodies to sars - cov were detected in maternal serum , cord blood , and breast milk by enzyme immunoassay and indirect immunofluorescence assay ( table ) .
sars , severe acute respiratory syndrome ; rt - pcr , reverse transcriptase  polymerase chain reaction ; nd , not done . 
all specimens listed were collected 127 days after onset of the case - patient s illness with the exception of breast milk , which was collected 131 days after illness onset . 
postdelivery placenta also underwent immunohistochemical ( ihc ) staining ; there was no ihc evidence of sars - cov .
on the basis of previous reports from hong kong , sars infection can be associated with critical maternal illness , spontaneous abortion , or maternal death ( 9,12 ) .
we have described a serious sars - associated illness that necessitated mechanical ventilation in a pregnant case - patient .
her pregnancy was also complicated by placenta previa and gestational diabetes  two conditions that she was at increased risk of developing because of advanced maternal age ( 13 ) .
however , at the time of delivery , clinical specimens from the infant were not available for sars - cov testing .
all healthcare workers involved in the delivery and subsequent care of the infant have remained healthy .
however , serologic testing for sars - cov infection was not performed on these persons .
the infant was delivered by cesarean section with contact , droplet , and airborne precautions in place ( i.e. , staff wore fit - tested n95 respirators and the cesarean section took place in a negative - pressure operating room ) .
since sars - cov was not detected in specimens collected at delivery and the patient delivered months after her illness onset , it is not clear if such precautions were necessary .
however , other patients have demonstrated viral shedding in feces ( 14,15 ) and peritoneal fluid ( 16 ) , suggesting that sars - cov may be present in other body fluids and hence , transmission during vaginal and cesarean deliveries is plausible .
the presence , in this case , of sars - cov antibodies in cord blood and breast milk raises the issue of whether sars - cov infection during pregnancy results in passive immunity .
serial serologic testing of newborn clinical specimens and breast milk may provide a better understanding of the natural history of the fetal and newborn immune response to sars - cov infection during pregnancy .
this report , in conjunction with the reports from hong kong ( 9,12 ) , provides an initial view of the spectrum of illness and outcomes associated with pregnancy - related sars - cov infection . a variety of factors might contribute to this range of outcomes ( e.g. , timing of sars - cov exposure during pregnancy ; use of steroids , ribavirin , or both ; differences in host immune response ; the presence of coexisting conditions ) .
more comprehensive epidemiologic and clinical summaries about the course of other sars - affected pregnancies and long - term follow - up of infants are needed to fully define the pregnancy - related risks of this infection .
data on larger numbers of pregnant women infected with sars - cov may help refine infection - control strategies and provide a sound basis for clinical guidelines to manage future cases .
we report a laboratory - confirmed case of severe acute respiratory syndrome ( sars ) in a pregnant woman . 
 although the patient had respiratory failure , a healthy infant was subsequently delivered , and the mother is now well . 
 there was no evidence of viral shedding at delivery . 
 antibodies to sars virus were detected in cord blood and breast milk .