Batista et al used SVM and RF, and the best results 
are 0.87 of AUC and 0.72 of F1-score. According to 
Alakus et al, the best accuracy, AUC and F1-score of 
CNN+LSTM are 0.9230, 0.90 and 0.93, respectively. 
Our proposed CNN+Bi-GRU model provides the best 
performance whose accuracy, AUC and F1-score are 
0.9415, 0.91 and 0.9417, both higher than SVM, RF 
and  CNN+LSTM.  Overall,  the  performance  of 
CNN+Bi-GRU is better than the other existing mod-
els. 
5  CONCLUSIONS 
In  this paper, four  hybrid deep  learning  models are 
proposed  to  predict  COVID-19  infection  based  on 
blood  test,  i.e.,  CNN+GRU,  CNN+Bi-RNN, 
CNN+Bi-LSTM and  CNN+BiGRU. Besides, 18  in-
dicators from the blood test data are selected as fea-
tures,  and  five  metrics  are  adopted  to  evaluate  the 
model performance, namely accuracy, F1-score, pre-
cision, recall and AUC. Experiment results show that 
CNN+Bi-GRU  model  outperforms  the  proposes 
models of Alakus et al in terms of all the evaluation 
metrics. We believe that CNN+Bi-GRU  model will 
be an effective supplementary method for COVID-19 
diagnosis based on blood test. In the future, we will 
continue explore deep learning models for COVID-
19 prediction and design novel prediction models. 
ACKNOWLEDGMENT 
This work was supported in part by the Macao Poly-
technic Institute – Big Data-Driven Intelligent Com-
puting (RP/ESCA-05/2020). 
REFERENCES 
Johns  Hopkins  University  (2021).  COVID-19  infection 
Dashboard from Johns Hopkins University System Sci-
ence  and  Engineering  Centre.  Retrieved  from 
https://www.arcgis.com/apps/opsdashboard/in-
dex.html#/bda7594740fd40299423467b48e9ecf6 
World Health Organization (2020). Disease Outbreak News 
of 2020 December: Important Notices of SARS-CoV2 
Variant  -  Unite  Kingdom.  Retrieved  from 
https://www.thenewsmarket.com/news/disease-out-
break-news--sars-cov-2-variant---united-king-
dom/s/c25fc68f-3676-4741-abd1-928b7aec0eb9 
World  Health  Organization  (2021).  Coronavirus  disease 
(COVID-19)  advice  for  the  public.  Retrieved  from 
https://www.who.int/emergencies/diseases/novel-coro-
navirus-2019/advice-for-public 
Ferrari, D., Sabetta, E., Ceriotti, D., Motta, A., Strollo, M., 
Banfi, G., & Locatelli, M. (2020). Routine blood anal-
ysis greatly reduces the false-negative rate of RT-PCR 
testing  for  COVID-19.  Acta  Bio  Medica:  Atenei 
Parmensis, 91(3), e2020003. 
Peeling, R. W., Wedderburn, C. J., Garcia, P. J., Boeras, D., 
Fongwen,  N.,  Nkengasong,  J.,  &  Heymann,  D.  L. 
(2020). Serology testing in the COVID-19 pandemic re-
sponse. The Lancet Infectious Diseases. 
World  Health  Organization  (2020).  Coronavirus  disease 
(COVID-19),  health  topics.  Retrieved  from 
https://www.who.int/emergencies/diseases/novel-coro-
navirus-2019/question-and-answers-hub/q-a-de-
tail/coronavirus-disease-covid-19 
Wynants, L., Van Calster, B., Collins, G. S., Riley, R. D., 
Heinze, G., Schuit, E., & van Smeden, M. (2020). Pre-
diction models for diagnosis and prognosis of covid-19: 
systematic review and critical appraisal. bmj, 369. 
Amanda, B., Meredith, G. (2020). How long does it take to 
get  COVID-19  test  results?  Retrieved  from 
https://www.medicalnewstoday.com/articles/corona-
virus-covid-19-test-results-how-long 
He, J., Baxter, S. L., Xu, J., Xu, J., Zhou, X., & Zhang, K. 
(2019). The practical implementation of artificial intel-
ligence  technologies  in  medicine.  Nature  medicine, 
25(1), 30-36. 
Jiang, X., Coffee, M., Bari, A., Wang, J., Jiang, X., Huang, 
J.,  &  Huang,  Y.  (2020).  Towards  an  artificial  intelli-
gence framework for data-driven prediction of corona-
virus clinical severity. CMC: Computers, Materials & 
Continua, 63, 537-51. 
De Moraes Batista, A. F., Miraglia, J. L., Donato, T. H. R., 
& Chiavegatto Filho, A. D. P. (2020). COVID-19 diag-
nosis prediction in emergency care patients: a machine 
learning approach. medRxiv. 
Cabitza, F., Campagner, A., Ferrari, D., Di Resta, C., 
Ceriotti, D., Sabetta, E., ... & Carobene, A. (2020). De-
velopment, evaluation, and validation of machine learn-
ing models for COVID-19  detection  based  on  routine 
blood tests. Clinical Chemistry and Laboratory Medi-
cine (CCLM), 1(ahead-of-print). 
Alakus, T. B., & Turkoglu, I. (2020). Comparison of deep 
learning  approaches  to  predict  COVID-19  infection. 
Chaos, Solitons & Fractals, 140, 110120. 
Dlamini, Z., Francies, F. Z., Hull, R., & Marima, R. (2020). 
Artificial intelligence (AI) and big  data in cancer and 
precision oncology. Computational and Structural Bio-
technology Journal. 
Cui, R., Liu, M., & Alzheimer's Disease Neuroimaging In-
itiative.  (2019).  RNN-based  longitudinal  analysis  for 
diagnosis of Alzheimer’s disease. Computerized Medi-
cal Imaging and Graphics, 73, 1-10. 
Sainath, T.  N.,  Vinyals, O.,  Senior,  A., &  Sak, H.  (2015, 
April).  Convolutional,  long  short-term  memory  fully 
connected deep neural networks. In 2015 IEEE Interna-
tional Conference on Acoustics, Speech and Signal Pro-
cessing (ICASSP) (pp. 4580-4584). IEEE.