Transmission of severe acute respiratory syndrome coronavirus 2 via fecal-oral: Current knowledge

Table 1 Main gastrointestinal manifestations in the articles discussed in the text

Ref.	Any GI symptom	Diarrhea	Nausea/vomiting	Abdominal pain	Loss of appetite
Redd et al[35]	195	107	84	46	110
Lin et al[36]	58	23	17	ND	17
Pan et al[38]	103	35	4	2	81
Jin et al[40]	74	53	ND	ND	ND
Sulaiman et al[41]	78	41	32	42	40

GI: Gastrointestinal; ND: Not described.

Table 2 Detection of severe acute respiratory syndrome by coronavirus 2 RNA in anal swabs or fecal sample

					SARS-CoV-2 RNA
n	Ref.	Country	n	Age	RT-PCR	Stool	PSDI	Respiratory	PRDI	Relevance information
1	Xie et al[56]	China	4	4-9 yr	AS-PS	4/4	8-33 d	4/4	11-21 d	One patient with positive stool RNA 54 d after hospital admission
2	Ge et al[57]	China	1	55 yr	FS-RS	1/1	18 d	1/1	7 d	Positive stool RNA 22 d after negative respiratory
3	Lo et al[58]	China	10	27-64 yr	FS-PS	10/10	5-19 d	10/10	9-24 d	Some patients had positive stool even with negative respiratory
4	Zhang et al[17]	China	3	6-9 yr	AS-PS	3/3	16-20 d	3/3	7-14 d	The anal swab was positive after 10 d of discharge
5	Liu et al[59]	China	9	NR	AS-PS	8/9	28-66 d	9/9	6–24 d	Positive stool RNA 46 d after discharge
6	Wang et al[60]	China	5	35-56 yr	FS-PS	5/5	11-30 d	5/5	5-9 d	Even after a negative respiratory test, IgM was positive on 2 consecutive occasions
7	Wang X et al[61]	China	3	24-42 yr	FS-PS	2/3	30-36 d	3/3	15-29 d	-
8	Xing et al[62]	China	3	ND	FS-PS	3/3	8 d-4 wk	3/3	2 wk	Positive stool RNA 8-20 d after negative respiratory
9	Chen et al[63]	China	42	42-62 yr	AS-FS	28/42	1-24 d	42/42	1-19 d	Eighteen patients remained positive for viral RNA in the feces after the pharyngeal swabs turned negative
10	Wu et al[64]	China	74	ND	FS-PS	33/74	27, 9 d	74/74	16, 7 d	Fecal positive 47 d after the onset of the first symptoms
11	Li et al[65]	China	13	33-73 yr	FS-RS	5/13	Until 38 d	13/13	5-14 d	Positive stool RNA 14-15 d after negative respiratory
12	Du et al[66]	China	10	9 mo-14 yr	FS-PS	7/10	Mean 34.43 d	10/10	Mean 9 d	Seven patients positive stool RNA 2 wk after discharge but negative respiratory and urine
13	Xiao et al[16]	China	73	10 mo-78 yr	FS-PS	39/73	1-12 d	ND	ND	Seventeen patients positive stool RNA after negative respiratory
14	Xu et al[67]	China	10	2 mo-15 yr	AS-PS	8/10	1-27 d	10/10	1-21	Eight patients positive stool RNA after negative respiratory
15	Fan et al[68]	China	1	3 mo	AS-PS	1/1	1-28 d	1/1	1-14	Positive stool RNA 14 d after negative respiratory

SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2; AS: Anal swabs; PS: Pharyngeal swabs; FS: Fecal sample; RS: Respiratory samples; PSDI: Positive stool duration interval; PRDI: Positive respiratory duration interval; ND: Not described; IgM: Immunoglobulin M.

Table 3 Detection of severe acute respiratory syndrome by coronavirus 2 RNA in water systems

Ref.	Country	Wastewater type	Main findings
Medema et al[96]	The Netherlands	Sewage	Sewage samples of six cities and the airport were tested: (1) February: No SARS-CoV-2 RNA was detected; and (2) March: SARS-CoV-2 RNA detection increased concomitant with the increase in COVID-19 prevalence
Ahmed et al[97]	Australia	Wastewater in a catchment	Two positive detections within a 6-d period from the same wastewater treatment plant
Kumar et al[98]	India	Wastewater Treatment Plant	Increase in SARS-CoV-2 RNA samples was concomitant with the increase in the number of active COVID-19 patients in the city
Wurtzer et al[99]	France	Wastewater treatment plant (raw and treated wastewater samples)	Raw wastewater samples: all positive for SARS-CoV2; Treated wastewater samples: 6 out of 8 positive for SARS-CoV2
Randazzo et al[100]	Spain	Wastewater treatments plants	(1) Influent samples: 35 of 42 were positive for SARS-CoV-2; (2) Effluent secondary treated samples: 2 of 18 were tested positive; and (3) Effluent tertiary treated samples: 0 of 12 tested positive
Kocamemi et al[101]	Turkey	Wastewater treatment plants (primary sludge and waste activated sludge)	SARS-CoV-2 RNA was detected quantitatively from all samples.
Guerrero-Latorre et al[102]	Ecuador	River	SARS-CoV-2 RNA was detected in the three locations
Zhang et al[103]	China	Septic tanks	SARS-CoV-2 RNA was detected in septic tanks after disinfection with sodium hypochlorite
Ahmed et al[104]	United States	Wastewater treatment plants	Two out of 15 wastewater samples tested positive
Haramoto et al[105]	Japan	River, wastewater treatment plants	One of 5 secondary-treated wastewater samples tested positive
La Rosa et al[106]	Italy	Sewage	Six out of 12 samples tested positive.
Hasan et al[107]	United Arab Emirates	Sewage, wastewater treatment plants, pumping stations	SARS-CoV-2 RNA was detected in 85% of untreated wastewater samples; SARS-CoV-2 RNA was not detected in wastewater treatment plants.

WHO: Pneumonia cases of unknown etiology[50]. SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2; COVID-19: Coronavirus disease 2019.