Table 1.

Historical lung histopathology data in mouse preclinical studies for SARS and MERS vaccines. Comparison of eosinophil infiltration induced by (A) different SARS vaccines and (B) different adjuvants for the whole virus MERS vaccine.

Vaccine type	Average eosinophil infiltration score	reference
(A) SARS Vaccine
Study 1 (Score scale: 0–4) Score based on percent eosinophils on histologic evaluation. 7–8 mice per group. 5 microscopy fields for each mouse lung were evaluated.
Whole virus (DIV)	~3	Tseng et al., 2012[12]
Spike protein	~2
Spike protein virus-like particle	>3
Whole virus (DIV) with alum	~2
Spike protein with alum	~1.5
Spike protein virus-like particle with alum	>3
PBS control	~0
Study 2 (Score scale: 0–3) Score for eosinophils as percent of infiltrating cells for each vaccine dosage group. N= 7–8 per group. 10 to 20 microscopy fields for each mouse lung were scored. Scoring: 0= ,5% of cells, 1= 5–10% of cells, 2= 10–20% of cells, 3= 20% of cells.
Spike protein	~1.5	Tseng et al., 2012[12]
Whole virus (DIV)	~2.5
Whole virus (BPV)	Not available
Spike protein with alum	~1.5
Whole virus (DIV) with alum	~2.5
Whole virus (BPV) with alum	~2.5
PBS control	0
(B) MERS Vaccine
Study 1 (Score scale: 0–3) 0- no pathology, 1- mild, 2- moderate, and 3-severe.
Alum alone	0	Agrawal et al., 2016[39]
MF59-like adjuvant alone	0
Whole virus with alum	2
Whole virus with MF59-like adjuvant	2
Whole virus	2

DIV: double-inactivated whole virus vaccine, BPV: Beta propiolactone-inactivated whole virus vaccine.